Adding a '--clean-publisher-objects' option to 'pg_createsubscriber' utility.

From 728184a84167d5648f4ac687fe130b8fb5c62e98 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 23 Jan 2025 12:39:03 +0530
Subject: [PATCH v2] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-publisher-objects' option in the
'pg_createsubscriber utility'.
This feature ensures a clean and streamlined setup of logical replication by
removing stale or unnecessary publications from the subscriber node.
These publications, replicated during streaming replication, become redundant
after converting to logical replication and serve no further purpose.
By ensuring that outdated publications are removed, it helps avoid potential
conflicts and simplifies replication management.

A new 'drop_all_publications()' function is added to fetch and drop all
publications on the subscriber node.
Since this cleanup is not required when upgrading streaming replication
clusters,this feature is supported only when the '--cleanup-publisher-objects'
option is specified, allowing users to choose accordingly.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     | 11 +++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 74 ++++++++++++++++++-
 .../t/040_pg_createsubscriber.pl              | 21 +++++-
 3 files changed, 103 insertions(+), 3 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index 26b8e64a4e..7c45fe960e 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-C</option></term>
+     <term><option>--cleanup-publisher-objects</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications on the subscriber node before creating
+       a subscription.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index faf18ccf13..c49e987f69 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		cleanup_publisher_objects;	/* Drop all publications */
 };
 
 struct LogicalRepInfo
@@ -98,6 +99,7 @@ static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_all_publications(const struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -220,6 +222,7 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -C  --cleanup-publisher-objects drop all publications on the logical replica\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1860,11 +1863,72 @@ enable_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+static void
+drop_all_publications(const struct LogicalRepInfo *dbinfo)
+{
+	char	   *search_query = "SELECT pubname FROM pg_catalog.pg_publication;";
+
+	for (int i = 0; i < num_dbs; i++)
+	{
+		PGconn	   *conn;
+		PGresult   *res;
+		int			num_rows;
+		PQExpBuffer query = createPQExpBuffer();
+
+		/* Connect to the subscriber */
+		conn = connect_database(dbinfo[i].subconninfo, true);
+
+		/* Fetch all publications */
+		res = PQexec(conn, search_query);
+
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_warning("could not obtain publication information: %s",
+						   PQresultErrorMessage(res));
+
+			PQclear(res);
+			disconnect_database(conn, false);
+			continue;
+		}
+
+		num_rows = PQntuples(res);
+
+		for (int j = 0; j < num_rows; j++)
+		{
+			char	   *pubname = PQgetvalue(res, j, 0);
+			PGresult   *res_for_drop;
+
+			pg_log_debug("dropping publication \"%s\"", pubname);
+
+			appendPQExpBuffer(query, "DROP PUBLICATION %s;", pubname);
+
+			if (!dry_run)
+			{
+				res_for_drop = PQexec(conn, query->data);
+
+				if (PQresultStatus(res_for_drop) != PGRES_COMMAND_OK)
+				{
+					pg_log_warning("could not drop publication \"%s\": %s",
+								   pubname, PQresultErrorMessage(res));
+				}
+
+				PQclear(res_for_drop);
+			}
+
+			resetPQExpBuffer(query);
+		}
+
+		disconnect_database(conn, false);
+		destroyPQExpBuffer(query);
+	}
+}
+
 int
 main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-publisher-objects", no_argument, NULL, 'C'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1927,6 +1991,7 @@ main(int argc, char **argv)
 	opt.socket_dir = NULL;
 	opt.sub_port = DEFAULT_SUB_PORT;
 	opt.sub_username = NULL;
+	opt.cleanup_publisher_objects = false;
 	opt.database_names = (SimpleStringList)
 	{
 		0
@@ -1949,11 +2014,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "Cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'C':
+				opt.cleanup_publisher_objects = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2237,6 +2305,10 @@ main(int argc, char **argv)
 	/* Remove failover replication slots if they exist on subscriber */
 	drop_failover_replication_slots(dbinfo);
 
+	/* Drop publications from the subscriber if requested */
+	if (opt.cleanup_publisher_objects)
+		drop_all_publications(dbinfo);
+
 	/* Stop the subscriber */
 	pg_log_info("stopping the subscriber");
 	stop_standby_server(subscriber_dir);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b..a609807357 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -371,8 +371,18 @@ command_ok(
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Create publications to test it's removal
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub FOR ALL TABLES;");
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub2 FOR ALL TABLES;");
+
+# Verify the existing publications
+my $pub_count_before =
+  $node_p->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;");
+is($pub_count_before, '2',
+	'two publications created before --cleanup-publisher-objects is run');
+
+# Run pg_createsubscriber on node S using --cleanup-publisher-objects.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -388,6 +398,7 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-publisher-objects',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,6 +417,12 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+my $pub_count_after =
+  $node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;");
+is($pub_count_after, '0',
+	'all publications dropped after --cleanup-publisher-objects is run');
+
 # Confirm the pre-existing subscription has been removed
 $result = $node_s->safe_psql(
 	'postgres', qq(
-- 
2.41.0.windows.3

From 1dc2abc77278b6847f016348fedbd4d060fe6a97 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 23 Jan 2025 12:39:03 +0530
Subject: [PATCH v3] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-publisher-objects' option in the
'pg_createsubscriber utility'.
This feature ensures a clean and streamlined setup of logical replication by
removing stale or unnecessary publications from the subscriber node.
These publications, replicated during streaming replication, become redundant
after converting to logical replication and serve no further purpose.
By ensuring that outdated publications are removed, it helps avoid potential
conflicts and simplifies replication management.

A new 'drop_all_publications()' function is added to fetch and drop all
publications on the subscriber node.
Since this cleanup is not required when upgrading streaming replication
clusters,this feature is supported only when the '--cleanup-publisher-objects'
option is specified, allowing users to choose accordingly.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     | 11 +++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 77 ++++++++++++++++++-
 .../t/040_pg_createsubscriber.pl              | 23 +++++-
 3 files changed, 108 insertions(+), 3 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index 26b8e64a4e..7c45fe960e 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-C</option></term>
+     <term><option>--cleanup-publisher-objects</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications on the subscriber node before creating
+       a subscription.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index faf18ccf13..d4cb3ebd36 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		cleanup_publisher_objects;	/* drop all publications */
 };
 
 struct LogicalRepInfo
@@ -98,6 +99,7 @@ static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_all_publications(const struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -220,6 +222,7 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -C  --cleanup-publisher-objects drop all publications on the logical replica\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1860,11 +1863,75 @@ enable_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/* Drops all existing logical replication publications from all subscriber
+ * databases
+ */
+static void
+drop_all_publications(const struct LogicalRepInfo *dbinfo)
+{
+	const char *search_query = "SELECT pubname FROM pg_catalog.pg_publication;";
+
+	for (int i = 0; i < num_dbs; i++)
+	{
+		PGconn	   *conn;
+		PGresult   *res;
+		int			num_rows;
+		PQExpBuffer query = createPQExpBuffer();
+
+		/* Connect to the subscriber */
+		conn = connect_database(dbinfo[i].subconninfo, true);
+
+		/* Fetch all publications */
+		res = PQexec(conn, search_query);
+
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_warning("could not obtain publication information: %s",
+						   PQresultErrorMessage(res));
+
+			PQclear(res);
+			disconnect_database(conn, false);
+			continue;
+		}
+
+		num_rows = PQntuples(res);
+
+		for (int j = 0; j < num_rows; j++)
+		{
+			char	   *pubname = PQgetvalue(res, j, 0);
+			PGresult   *res_for_drop;
+
+			pg_log_debug("dropping publication \"%s\"", pubname);
+
+			appendPQExpBuffer(query, "DROP PUBLICATION %s;", pubname);
+
+			if (!dry_run)
+			{
+				res_for_drop = PQexec(conn, query->data);
+
+				if (PQresultStatus(res_for_drop) != PGRES_COMMAND_OK)
+				{
+					pg_log_warning("could not drop publication \"%s\": %s",
+								   pubname, PQresultErrorMessage(res));
+				}
+
+				PQclear(res_for_drop);
+			}
+
+			resetPQExpBuffer(query);
+		}
+
+		disconnect_database(conn, false);
+		destroyPQExpBuffer(query);
+	}
+}
+
 int
 main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-publisher-objects", no_argument, NULL, 'C'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1927,6 +1994,7 @@ main(int argc, char **argv)
 	opt.socket_dir = NULL;
 	opt.sub_port = DEFAULT_SUB_PORT;
 	opt.sub_username = NULL;
+	opt.cleanup_publisher_objects = false;
 	opt.database_names = (SimpleStringList)
 	{
 		0
@@ -1949,11 +2017,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "Cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'C':
+				opt.cleanup_publisher_objects = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2237,6 +2308,10 @@ main(int argc, char **argv)
 	/* Remove failover replication slots if they exist on subscriber */
 	drop_failover_replication_slots(dbinfo);
 
+	/* Drop publications from the subscriber if requested */
+	if (opt.cleanup_publisher_objects)
+		drop_all_publications(dbinfo);
+
 	/* Stop the subscriber */
 	pg_log_info("stopping the subscriber");
 	stop_standby_server(subscriber_dir);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b..9f2543bf7a 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -371,8 +371,20 @@ command_ok(
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+$node_s->start;
+# Create publications to test it's removal
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub FOR ALL TABLES;");
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub2 FOR ALL TABLES;");
+
+# Verify the existing publications
+my $pub_count_before =
+  $node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;");
+is($pub_count_before, '2',
+	'two publications created before --cleanup-publisher-objects is run');
+
+$node_s->stop;
+# Run pg_createsubscriber on node S using --cleanup-publisher-objects.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -388,6 +400,7 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-publisher-objects',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,6 +419,12 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+my $pub_count_after =
+  $node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;");
+is($pub_count_after, '0',
+	'all publications dropped after --cleanup-publisher-objects is run');
+
 # Confirm the pre-existing subscription has been removed
 $result = $node_s->safe_psql(
 	'postgres', qq(
-- 
2.34.1

From 6610d0115e8f1d3e91daa08083cab6396979ca2c Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 23 Jan 2025 12:39:03 +0530
Subject: [PATCH v4] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber utility'.
This feature ensures a clean and streamlined setup of logical replication by
removing stale or unnecessary publications from the subscriber node.
These publications, replicated during streaming replication, become redundant
after converting to logical replication and serve no further purpose.
By ensuring that outdated publications are removed, it helps avoid potential
conflicts and simplifies replication management.

Since this cleanup is not required when upgrading streaming replication
clusters, this feature is supported only when the
'--cleanup-existing-publications' option is specified, allowing users to
choose accordingly.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 109 ++++++++++++++----
 .../t/040_pg_createsubscriber.pl              |  24 +++-
 3 files changed, 118 insertions(+), 26 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index 26b8e64a4e0..1ebe8e09081 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications on the subscriber node before creating
+       a subscription.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index faf18ccf131..ee0bd73fe78 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		cleanup_existing_publications;	/* drop all publications */
 };
 
 struct LogicalRepInfo
@@ -79,7 +80,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool cleanup_existing_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -97,7 +99,8 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+							 bool cleanup_existing_publications);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -180,7 +183,7 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfo[i]);
+					drop_publication(conn, &dbinfo[i], false);
 				if (dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfo[i], dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -220,6 +223,7 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1138,7 +1142,8 @@ check_and_drop_existing_subscriptions(PGconn *conn,
  * replication setup.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1159,8 +1164,10 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		drop_publication(conn, &dbinfo[i], cleanup_existing_publications);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1623,22 +1630,74 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
  * Remove publication if it couldn't finish all steps.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+				 bool cleanup_existing_publications)
 {
-	PQExpBuffer str = createPQExpBuffer();
+	PQExpBuffer targets = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
+	int			count = 0;
+	PQExpBuffer str;
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/*
+	 * Gather all dropping publications. Usually, the target is the
+	 * publication created by the command, but if requested, all publications
+	 * are.
+	 */
+	if (cleanup_existing_publications)
+	{
+		const char *search_query =
+			"SELECT pubname FROM pg_catalog.pg_publication;";
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+		res = PQexec(conn, search_query);
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+			PQclear(res);
+			dbinfo->made_publication = false;	/* don't try again. */
 
-	pg_free(pubname_esc);
+			/*
+			 * Don't disconnect and exit here. This routine is used by primary
+			 * (cleanup publication / replication slot due to an error) and
+			 * subscriber (remove the replicated publications). In both cases,
+			 * it can continue and provide instructions for the user to remove
+			 * it later if cleanup fails.
+			 */
+			destroyPQExpBuffer(targets);
+			return;
+		}
+
+		/* Append all the publication's name into the target string */
+		for (int i = 0; i < PQntuples(res); i++)
+		{
+			if (i > 0)
+				appendPQExpBufferStr(targets, ", ");
+
+			appendPQExpBuffer(targets, "%s", PQgetvalue(res, i, 0));
+			count++;
+		}
+
+		PQclear(res);
+	}
+	else
+	{
+		appendPQExpBufferStr(targets,
+							 PQescapeIdentifier(conn, dbinfo->pubname,
+												strlen(dbinfo->pubname)));
+		count++;
+	}
+
+	pg_log_info(ngettext("dropping publication \"%s\" in database \"%s\"",
+						 "dropping publications \"%s\" in database \"%s\"",
+						 count),
+				targets->data, dbinfo->dbname);
+
+	/* Construct an SQL command and run it */
+	str = createPQExpBuffer();
+	appendPQExpBuffer(str, "DROP PUBLICATION %s", targets->data);
 
 	pg_log_debug("command is: %s", str->data);
 
@@ -1647,22 +1706,19 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		res = PQexec(conn, str->data);
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
+			pg_log_error(ngettext("could not drop publication \"%s\" in database \"%s\": %s",
+								  "could not drop publications \"%s\" in database \"%s\": %s",
+								  count),
+						 targets->data, dbinfo->dbname, PQresultErrorMessage(res));
 			dbinfo->made_publication = false;	/* don't try again. */
 
-			/*
-			 * Don't disconnect and exit here. This routine is used by primary
-			 * (cleanup publication / replication slot due to an error) and
-			 * subscriber (remove the replicated publications). In both cases,
-			 * it can continue and provide instructions for the user to remove
-			 * it later if cleanup fails.
-			 */
+			/* Don't disconnect and exit here as discussed before */
 		}
 		PQclear(res);
 	}
 
 	destroyPQExpBuffer(str);
+	destroyPQExpBuffer(targets);
 }
 
 /*
@@ -1865,6 +1921,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1927,6 +1984,7 @@ main(int argc, char **argv)
 	opt.socket_dir = NULL;
 	opt.sub_port = DEFAULT_SUB_PORT;
 	opt.sub_username = NULL;
+	opt.cleanup_existing_publications = false;
 	opt.database_names = (SimpleStringList)
 	{
 		0
@@ -1949,11 +2007,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.cleanup_existing_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2229,7 +2290,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfo, consistent_lsn);
+	setup_subscriber(dbinfo, consistent_lsn, opt.cleanup_existing_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b7..aeb58017d97 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,19 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create publications to test it's removal
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub FOR ALL TABLES;");
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub2 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s);
+
+# Verify the existing publications
+my $pub_count_before =
+  $node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;");
+is($pub_count_before, '2',
+	'two publications created before --cleanup-existing-publications is run');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -371,8 +384,8 @@ command_ok(
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using --cleanup-existing-publications.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -388,6 +401,7 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,6 +420,12 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+my $pub_count_after =
+  $node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;");
+is($pub_count_after, '0',
+	'all publications dropped after --cleanup-existing-publications is run');
+
 # Confirm the pre-existing subscription has been removed
 $result = $node_s->safe_psql(
 	'postgres', qq(
-- 
2.41.0.windows.3

From 50f748e108953e1de31bc17590d5687a95c39585 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 13 Feb 2025 09:25:11 +0530
Subject: [PATCH v5] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber utility'.
This feature ensures a clean and streamlined setup of logical replication by
removing stale or unnecessary publications from the subscriber node.
These publications, replicated during streaming replication, become redundant
after converting to logical replication and serve no further purpose.
By ensuring that outdated publications are removed, it helps avoid potential
conflicts and simplifies replication management.

Since this cleanup is not required when upgrading streaming replication
clusters, this feature is supported only when the
'--cleanup-existing-publications' option is specified, allowing users to
choose accordingly.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  10 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 119 ++++++++++++++----
 .../t/040_pg_createsubscriber.pl              |  21 +++-
 3 files changed, 122 insertions(+), 28 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index 26b8e64a4e..c2d4e376e8 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,16 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 2d881d54f5..187844103e 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		cleanup_existing_publications;	/* drop all publications */
 };
 
 struct LogicalRepInfo
@@ -79,7 +80,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool cleanup_existing_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -97,7 +99,8 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+							 bool cleanup_existing_publications);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -180,7 +183,7 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfo[i]);
+					drop_publication(conn, &dbinfo[i], false);
 				if (dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfo[i], dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -220,6 +223,7 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1139,7 +1143,8 @@ check_and_drop_existing_subscriptions(PGconn *conn,
  * replication setup.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1160,8 +1165,10 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		drop_publication(conn, &dbinfo[i], cleanup_existing_publications);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1621,25 +1628,83 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Remove publication if it couldn't finish all steps or if cleanup of
+ * publications on the subscriber is required.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+				 bool cleanup_existing_publications)
 {
-	PQExpBuffer str = createPQExpBuffer();
+	PQExpBuffer targets = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
+	int			count = 0;
+	PQExpBuffer str;
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/*
+	 * Gather all dropping publications. Usually, the target is the
+	 * publication created by the command, but if requested, all publications
+	 * are.
+	 */
+	if (cleanup_existing_publications)
+	{
+		const char *search_query =
+			"SELECT pubname FROM pg_catalog.pg_publication;";
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+		res = PQexec(conn, search_query);
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+			PQclear(res);
+			dbinfo->made_publication = false;	/* don't try again. */
 
-	PQfreemem(pubname_esc);
+			/*
+			 * Don't disconnect and exit here. This routine is used by primary
+			 * (cleanup publication / replication slot due to an error) and
+			 * subscriber (remove the replicated publications). In both cases,
+			 * it can continue and provide instructions for the user to remove
+			 * it later if cleanup fails.
+			 */
+			return;
+		}
+
+		/* Append all the publication's name into the target string */
+		for (int i = 0; i < PQntuples(res); i++)
+		{
+			char	   *pubname_esc = PQescapeIdentifier(conn, PQgetvalue(res, i, 0),
+														 strlen(PQgetvalue(res, i, 0)));
+
+			if (i > 0)
+				appendPQExpBufferStr(targets, ", ");
+
+			appendPQExpBuffer(targets, "%s", pubname_esc);
+			PQfreemem(pubname_esc);
+			count++;
+		}
+
+		PQclear(res);
+	}
+	else
+	{
+		char	   *pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname,
+													 strlen(dbinfo->pubname));
+
+		appendPQExpBuffer(targets, "%s", pubname_esc);
+		PQfreemem(pubname_esc);
+
+		count++;
+	}
+
+	pg_log_info(ngettext("dropping publication %s in database \"%s\"",
+						 "dropping publications %s in database \"%s\"",
+						 count),
+				targets->data, dbinfo->dbname);
+
+	str = createPQExpBuffer();
+	appendPQExpBuffer(str, "DROP PUBLICATION %s", targets->data);
 
 	pg_log_debug("command is: %s", str->data);
 
@@ -1648,22 +1713,19 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		res = PQexec(conn, str->data);
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+			pg_log_error(ngettext("could not drop publication %s in database \"%s\": %s",
+								  "could not drop publications %s in database \"%s\": %s",
+								  count),
+						 targets->data, dbinfo->dbname, PQresultErrorMessage(res));
+			dbinfo->made_publication = false;
 
-			/*
-			 * Don't disconnect and exit here. This routine is used by primary
-			 * (cleanup publication / replication slot due to an error) and
-			 * subscriber (remove the replicated publications). In both cases,
-			 * it can continue and provide instructions for the user to remove
-			 * it later if cleanup fails.
-			 */
+			/* Don't disconnect and exit here as discussed before */
 		}
 		PQclear(res);
 	}
 
 	destroyPQExpBuffer(str);
+	destroyPQExpBuffer(targets);
 }
 
 /*
@@ -1866,6 +1928,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1933,6 +1996,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.cleanup_existing_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1950,11 +2014,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.cleanup_existing_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2230,7 +2297,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfo, consistent_lsn);
+	setup_subscriber(dbinfo, consistent_lsn, opt.cleanup_existing_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b..2c8e00b52a 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,17 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create publications to test it's removal
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub FOR ALL TABLES;");
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub2 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok( $node_s->poll_query_until(
+		$db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -371,8 +382,8 @@ command_ok(
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using --cleanup-existing-publications.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -388,6 +399,7 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,6 +418,11 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
+
 # Confirm the pre-existing subscription has been removed
 $result = $node_s->safe_psql(
 	'postgres', qq(
-- 
2.34.1

From 3895daeb67d22866052a5ff9aea7d2c32c6eb78a Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 13 Feb 2025 09:25:11 +0530
Subject: [PATCH v6] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber utility'.
This feature ensures a clean and streamlined setup of logical replication by
removing stale or unnecessary publications from the subscriber node.
These publications, replicated during streaming replication, become redundant
after converting to logical replication and serve no further purpose.
By ensuring that outdated publications are removed, it helps avoid potential
conflicts and simplifies replication management.

Since this cleanup is not required when upgrading streaming replication
clusters, this feature is supported only when the
'--cleanup-existing-publications' option is specified, allowing users to
choose accordingly.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  10 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 120 ++++++++++++++----
 .../t/040_pg_createsubscriber.pl              |  20 ++-
 3 files changed, 122 insertions(+), 28 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index 26b8e64a4e0..c2d4e376e87 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,16 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 2d881d54f5b..487105867f9 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		cleanup_existing_publications;	/* drop all publications */
 };
 
 struct LogicalRepInfo
@@ -79,7 +80,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool cleanup_existing_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -97,7 +99,8 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+							 bool cleanup_existing_publications);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -180,7 +183,7 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfo[i]);
+					drop_publication(conn, &dbinfo[i], false);
 				if (dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfo[i], dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -220,6 +223,8 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications\n"
+			 "                                  drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1139,7 +1144,8 @@ check_and_drop_existing_subscriptions(PGconn *conn,
  * replication setup.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1160,8 +1166,10 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		drop_publication(conn, &dbinfo[i], cleanup_existing_publications);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1621,25 +1629,83 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Remove all existing publications from specified databases on the target
+ * server.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+				 bool cleanup_existing_publications)
 {
-	PQExpBuffer str = createPQExpBuffer();
+	PQExpBuffer targets = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
+	int			count = 0;
+	PQExpBuffer str;
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/*
+	 * Gather all dropping publications. Usually, the target is the
+	 * publication created by the command, but if requested, all publications
+	 * are.
+	 */
+	if (cleanup_existing_publications)
+	{
+		const char *search_query =
+			"SELECT pubname FROM pg_catalog.pg_publication;";
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+		res = PQexec(conn, search_query);
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+			PQclear(res);
+			dbinfo->made_publication = false;	/* don't try again. */
 
-	PQfreemem(pubname_esc);
+			/*
+			 * Don't disconnect and exit here. This routine is used by primary
+			 * (cleanup publication / replication slot due to an error) and
+			 * subscriber (remove the replicated publications). In both cases,
+			 * it can continue and provide instructions for the user to remove
+			 * it later if cleanup fails.
+			 */
+			return;
+		}
+
+		/* Append all the publication's name into the target string */
+		for (int i = 0; i < PQntuples(res); i++)
+		{
+			char	   *pubname_esc = PQescapeIdentifier(conn, PQgetvalue(res, i, 0),
+														 strlen(PQgetvalue(res, i, 0)));
+
+			if (i > 0)
+				appendPQExpBufferStr(targets, ", ");
+
+			appendPQExpBuffer(targets, "%s", pubname_esc);
+			PQfreemem(pubname_esc);
+			count++;
+		}
+
+		PQclear(res);
+	}
+	else
+	{
+		char	   *pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname,
+													 strlen(dbinfo->pubname));
+
+		appendPQExpBuffer(targets, "%s", pubname_esc);
+		PQfreemem(pubname_esc);
+
+		count++;
+	}
+
+	pg_log_info(ngettext("dropping publication %s in database \"%s\"",
+						 "dropping publications %s in database \"%s\"",
+						 count),
+				targets->data, dbinfo->dbname);
+
+	str = createPQExpBuffer();
+	appendPQExpBuffer(str, "DROP PUBLICATION %s", targets->data);
 
 	pg_log_debug("command is: %s", str->data);
 
@@ -1648,22 +1714,19 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		res = PQexec(conn, str->data);
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+			pg_log_error(ngettext("could not drop publication %s in database \"%s\": %s",
+								  "could not drop publications %s in database \"%s\": %s",
+								  count),
+						 targets->data, dbinfo->dbname, PQresultErrorMessage(res));
+			dbinfo->made_publication = false;
 
-			/*
-			 * Don't disconnect and exit here. This routine is used by primary
-			 * (cleanup publication / replication slot due to an error) and
-			 * subscriber (remove the replicated publications). In both cases,
-			 * it can continue and provide instructions for the user to remove
-			 * it later if cleanup fails.
-			 */
+			/* Don't disconnect and exit here as discussed before */
 		}
 		PQclear(res);
 	}
 
 	destroyPQExpBuffer(str);
+	destroyPQExpBuffer(targets);
 }
 
 /*
@@ -1866,6 +1929,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1933,6 +1997,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.cleanup_existing_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1950,11 +2015,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.cleanup_existing_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2230,7 +2298,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfo, consistent_lsn);
+	setup_subscriber(dbinfo, consistent_lsn, opt.cleanup_existing_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b7..93af35daa0a 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,16 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create publications to test it's removal
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub FOR ALL TABLES;");
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub2 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok( $node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -371,8 +381,8 @@ command_ok(
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using --cleanup-existing-publications.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -388,6 +398,7 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,6 +417,11 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
+
 # Confirm the pre-existing subscription has been removed
 $result = $node_s->safe_psql(
 	'postgres', qq(
-- 
2.41.0.windows.3

From 6fbcbad905a0eb7298f518a99d01dc255e0387ee Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 13 Feb 2025 09:25:11 +0530
Subject: [PATCH v7] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber utility'.
This feature ensures a clean and streamlined setup of logical replication by
removing stale or unnecessary publications from the subscriber node.
These publications, replicated during streaming replication, become redundant
after converting to logical replication and serve no further purpose.
By ensuring that outdated publications are removed, it helps avoid potential
conflicts and simplifies replication management.

Since this cleanup is not required when upgrading streaming replication
clusters, this feature is supported only when the
'--cleanup-existing-publications' option is specified, allowing users to
choose accordingly.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 114 ++++++++++++++----
 .../t/040_pg_createsubscriber.pl              |  20 ++-
 3 files changed, 118 insertions(+), 27 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index 26b8e64a4e0..4750eacf990 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on tne target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 2d881d54f5b..9780349f05f 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		cleanup_existing_publications;	/* drop all publications */
 };
 
 struct LogicalRepInfo
@@ -79,7 +80,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool cleanup_existing_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -97,7 +99,8 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+							 bool cleanup_existing_publications);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -180,7 +183,7 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfo[i]);
+					drop_publication(conn, &dbinfo[i], false);
 				if (dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfo[i], dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -220,6 +223,8 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications\n"
+			 "                                  drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1139,7 +1144,8 @@ check_and_drop_existing_subscriptions(PGconn *conn,
  * replication setup.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1160,8 +1166,10 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		drop_publication(conn, &dbinfo[i], cleanup_existing_publications);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1624,22 +1632,76 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
  * Remove publication if it couldn't finish all steps.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+				 bool cleanup_existing_publications)
 {
-	PQExpBuffer str = createPQExpBuffer();
+	PQExpBuffer targets = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
+	int			count = 0;
+	PQExpBuffer str;
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/*
+	 * Gather all dropping publications. Usually, the target is the
+	 * publication created by the command, but if requested, all publications
+	 * are.
+	 */
+	if (cleanup_existing_publications)
+	{
+		res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+			PQclear(res);
+			dbinfo->made_publication = false;	/* don't try again. */
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+			/*
+			 * Don't disconnect and exit here. This routine is used by primary
+			 * (cleanup publication / replication slot due to an error) and
+			 * subscriber (remove the replicated publications). In both cases,
+			 * it can continue and provide instructions for the user to remove
+			 * it later if cleanup fails.
+			 */
+			return;
+		}
 
-	PQfreemem(pubname_esc);
+		/* Append all the publication's name into the target string */
+		for (int i = 0; i < PQntuples(res); i++)
+		{
+			char	   *pubname_esc = PQescapeIdentifier(conn, PQgetvalue(res, i, 0),
+														 strlen(PQgetvalue(res, i, 0)));
+
+			if (i > 0)
+				appendPQExpBufferStr(targets, ", ");
+
+			appendPQExpBuffer(targets, "%s", pubname_esc);
+			PQfreemem(pubname_esc);
+			count++;
+		}
+
+		PQclear(res);
+	}
+	else
+	{
+		char	   *pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname,
+													 strlen(dbinfo->pubname));
+
+		appendPQExpBuffer(targets, "%s", pubname_esc);
+		PQfreemem(pubname_esc);
+
+		count++;
+	}
+
+	pg_log_info(ngettext("dropping publication %s in database \"%s\"",
+						 "dropping publications %s in database \"%s\"",
+						 count),
+				targets->data, dbinfo->dbname);
+
+	str = createPQExpBuffer();
+	appendPQExpBuffer(str, "DROP PUBLICATION %s", targets->data);
 
 	pg_log_debug("command is: %s", str->data);
 
@@ -1648,22 +1710,19 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		res = PQexec(conn, str->data);
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+			pg_log_error(ngettext("could not drop publication %s in database \"%s\": %s",
+								  "could not drop publications %s in database \"%s\": %s",
+								  count),
+						 targets->data, dbinfo->dbname, PQresultErrorMessage(res));
+			dbinfo->made_publication = false;
 
-			/*
-			 * Don't disconnect and exit here. This routine is used by primary
-			 * (cleanup publication / replication slot due to an error) and
-			 * subscriber (remove the replicated publications). In both cases,
-			 * it can continue and provide instructions for the user to remove
-			 * it later if cleanup fails.
-			 */
+			/* Don't disconnect and exit here as discussed before */
 		}
 		PQclear(res);
 	}
 
 	destroyPQExpBuffer(str);
+	destroyPQExpBuffer(targets);
 }
 
 /*
@@ -1866,6 +1925,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1933,6 +1993,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.cleanup_existing_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1950,11 +2011,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.cleanup_existing_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2230,7 +2294,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfo, consistent_lsn);
+	setup_subscriber(dbinfo, consistent_lsn, opt.cleanup_existing_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b7..93af35daa0a 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,16 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create publications to test it's removal
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub FOR ALL TABLES;");
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub2 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok( $node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -371,8 +381,8 @@ command_ok(
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using --cleanup-existing-publications.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -388,6 +398,7 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,6 +417,11 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
+
 # Confirm the pre-existing subscription has been removed
 $result = $node_s->safe_psql(
 	'postgres', qq(
-- 
2.41.0.windows.3

From 1d219210a24ad7f83b1668598de82b3b4e829a64 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 13 Feb 2025 09:25:11 +0530
Subject: [PATCH v8] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

To prevent accidental removal of user-created publications on the subscriber,
this cleanup process only targets publications that existed on the source
server and were replicated to the subscriber.
Any manually created publications on the subscriber will remain intact.

This feature is optional and only takes effect when the
'--cleanup-existing-publications' option is explicitly specified.
Since publication cleanup is not required when upgrading streaming replication
clusters, this option provides users with the flexibility to enable or skip the
cleanup process as needed.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 120 +++++++++++++-----
 .../t/040_pg_createsubscriber.pl              |  20 ++-
 3 files changed, 117 insertions(+), 34 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index d56487fe2c..a98b583537 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 9fdf15e5ac..d8d24ab51a 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		drop_publications;	/* drop all publications */
 };
 
 struct LogicalRepInfo
@@ -79,7 +80,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool drop_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -97,6 +99,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void _drop_one_publication(PGconn *conn, const char *pubname,
+								  const char *dbname);
+static void drop_all_publications(PGconn *conn, const char *dbname);
 static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
@@ -220,6 +225,8 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications\n"
+			 "                                  drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1154,10 +1161,12 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' is true, existing publications on
+ * the subscriber will be dropped before creating new subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool drop_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1174,10 +1183,20 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 */
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
+		/* Drop all existing publications if requested */
+		if (drop_publications)
+		{
+			pg_log_info("Dropping all existing publications in database \"%s\"",
+						dbinfo[i].dbname);
+			drop_all_publications(conn, dbinfo[i].dbname);
+		}
+
 		/*
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
 		drop_publication(conn, &dbinfo[i]);
 
@@ -1642,50 +1661,82 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
-/*
- * Remove publication if it couldn't finish all steps.
- */
+/* Helper function to drop a single publication by name. */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+_drop_one_publication(PGconn *conn, const char *pubname, const char *dbname)
 {
-	PQExpBuffer str = createPQExpBuffer();
+	PQExpBuffer query = createPQExpBuffer();
 	PGresult   *res;
+
+	Assert(conn != NULL);
+	Assert(pubname != NULL);
+	Assert(dbname != NULL);
+
+	appendPQExpBuffer(query, "DROP PUBLICATION %s", pubname);
+	pg_log_debug("Executing: %s", query->data);
+	pg_log_info("Dropping publication %s in database \"%s\"", pubname, dbinfo->dbname);
+
+	if (!dry_run)
+	{
+		res = PQexec(conn, query->data);
+		if (PQresultStatus(res) != PGRES_COMMAND_OK)
+		{
+			pg_log_error("could not drop publication %s in database \"%s\": %s",
+						 pubname, dbname, PQresultErrorMessage(res));
+		}
+		PQclear(res);
+	}
+
+	destroyPQExpBuffer(query);
+}
+
+/* Drop a single publication, given in dbinfo. */
+static void
+drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
 	char	   *pubname_esc;
 
 	Assert(conn != NULL);
+	Assert(dbinfo != NULL);
+	Assert(dbinfo->pubname != NULL);
 
 	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
-
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+	_drop_one_publication(conn, pubname_esc, dbinfo->dbname);
 
 	PQfreemem(pubname_esc);
+}
 
-	pg_log_debug("command is: %s", str->data);
+/* Drop all publications in the database. */
+static void
+drop_all_publications(PGconn *conn, const char *dbname)
+{
+	PGresult   *res;
+	int			count = 0;
 
-	if (!dry_run)
+	Assert(conn != NULL);
+	Assert(dbname != NULL);
+
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
 	{
-		res = PQexec(conn, str->data);
-		if (PQresultStatus(res) != PGRES_COMMAND_OK)
-		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
-
-			/*
-			 * Don't disconnect and exit here. This routine is used by primary
-			 * (cleanup publication / replication slot due to an error) and
-			 * subscriber (remove the replicated publications). In both cases,
-			 * it can continue and provide instructions for the user to remove
-			 * it later if cleanup fails.
-			 */
-		}
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
 		PQclear(res);
+		return;
 	}
 
-	destroyPQExpBuffer(str);
+	for (int i = 0; i < PQntuples(res); i++)
+	{
+		char	   *pubname_esc = PQescapeIdentifier(conn, PQgetvalue(res, i, 0),
+													 strlen(PQgetvalue(res, i, 0)));
+
+		_drop_one_publication(conn, pubname_esc, dbname);
+		PQfreemem(pubname_esc);
+		count++;
+	}
+
+	PQclear(res);
 }
 
 /*
@@ -1888,6 +1939,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1955,6 +2007,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.drop_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1972,11 +2025,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.drop_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2252,7 +2308,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfo, consistent_lsn);
+	setup_subscriber(dbinfo, consistent_lsn, opt.drop_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b..3301b1425f 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,16 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create publications to test their removal
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub FOR ALL TABLES;");
+$node_p->safe_psql($db1, "CREATE PUBLICATION test_pub2 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok( $node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -371,8 +381,8 @@ command_ok(
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using --cleanup-existing-publications.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -388,6 +398,7 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,6 +417,11 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
+
 # Confirm the pre-existing subscription has been removed
 $result = $node_s->safe_psql(
 	'postgres', qq(
-- 
2.34.1

From df16f1aeb26263d48b77380c00df80ae396e8344 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 13 Feb 2025 09:25:11 +0530
Subject: [PATCH v9] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The --cleanup-existing-publications option allows users to remove replicated
publications from the subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed.
By default, publications are preserved to avoid unintended data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 103 ++++++++++++------
 .../t/040_pg_createsubscriber.pl              |  89 ++++++++++++++-
 3 files changed, 169 insertions(+), 34 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index d56487fe2c..a98b583537 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 9fdf15e5ac..5aa6fcccba 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		cleanup_existing_publications;	/* drop all publications */
 };
 
 struct LogicalRepInfo
@@ -79,7 +80,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool cleanup_existing_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -97,7 +99,11 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication_by_name(PGconn *conn, const char *pubname,
+									 const char *dbname);
+static void check_and_drop_existing_publications(PGconn *conn,
+												 const char *dbname,
+												 bool cleanup_existing_publications);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -180,7 +186,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfo[i]);
+					drop_publication_by_name(conn, dbinfo[i].pubname,
+											 dbinfo[i].dbname);
 				if (dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfo[i], dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -220,6 +227,8 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications\n"
+			 "                                  drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1154,10 +1163,12 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' is true, existing publications on
+ * the subscriber will be dropped before creating new subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1178,8 +1189,17 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (cleanup_existing_publications)
+		{
+			pg_log_info("cleaning up existing publications on the subscriber");
+			check_and_drop_existing_publications(conn, dbinfo[i].dbname,
+												 cleanup_existing_publications);
+		}
+		else
+			drop_publication_by_name(conn, dbinfo[i].pubname, dbinfo[i].dbname);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1643,49 +1663,63 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Check and drop existing publications on the subscriber if requested.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+check_and_drop_existing_publications(PGconn *conn, const char *dbname,
+									 bool cleanup_existing_publications)
 {
-	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
 
-	Assert(conn != NULL);
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbname);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication_by_name(conn, PQgetvalue(res, i, 0), dbname);
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbname);
+}
 
-	PQfreemem(pubname_esc);
+/* Drop a single publication, given in dbinfo. */
+static void
+drop_publication_by_name(PGconn *conn, const char *pubname, const char *dbname)
+{
+	PQExpBuffer query = createPQExpBuffer();
+	PGresult   *res;
 
-	pg_log_debug("command is: %s", str->data);
+	char	   *pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
+
+	appendPQExpBuffer(query, "DROP PUBLICATION %s", pubname_esc);
+	pg_log_info("dropping publication %s in database \"%s\"", pubname, dbname);
+	pg_log_debug("command is: %s", query->data);
 
 	if (!dry_run)
 	{
-		res = PQexec(conn, str->data);
+		res = PQexec(conn, query->data);
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
+			dbinfo->made_publication = false;
+		else
 		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
-
-			/*
-			 * Don't disconnect and exit here. This routine is used by primary
-			 * (cleanup publication / replication slot due to an error) and
-			 * subscriber (remove the replicated publications). In both cases,
-			 * it can continue and provide instructions for the user to remove
-			 * it later if cleanup fails.
-			 */
+			pg_log_error("could not drop publication %s in database \"%s\": %s",
+						 pubname, dbname, PQresultErrorMessage(res));
 		}
 		PQclear(res);
 	}
 
-	destroyPQExpBuffer(str);
+	PQfreemem(pubname_esc);
+	destroyPQExpBuffer(query);
 }
 
 /*
@@ -1888,6 +1922,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1955,6 +1990,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.cleanup_existing_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1972,11 +2008,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.cleanup_existing_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2252,7 +2291,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfo, consistent_lsn);
+	setup_subscriber(dbinfo, consistent_lsn, opt.cleanup_existing_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b..4da0c35260 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--cleanup-existing-publications'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok( $node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -371,8 +386,8 @@ command_ok(
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -388,6 +403,7 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,6 +422,11 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
+
 # Confirm the pre-existing subscription has been removed
 $result = $node_s->safe_psql(
 	'postgres', qq(
@@ -448,10 +469,74 @@ my $sysid_s = $node_s->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Set up node A as primary
+my $node_a = PostgreSQL::Test::Cluster->new('node_a');
+my $aconnstr = $node_a->connstr;
+$node_a->init(allows_streaming => 'logical');
+$node_a->append_conf('postgresql.conf', 'autovacuum = off');
+$node_a->start;
+
+# Set up node B as standby linking to node A
+$node_a->backup('backup_3');
+my $node_b = PostgreSQL::Test::Cluster->new('node_b');
+$node_b->init_from_backup($node_a, 'backup_3', has_streaming => 1);
+$node_b->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$aconnstr'
+       hot_standby_feedback = on
+       max_logical_replication_workers = 5
+       ]);
+$node_b->set_standby_mode();
+$node_b->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_a, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_a->safe_psql($db3, "CREATE PUBLICATION test_pub3 FOR ALL TABLES;");
+$node_a->safe_psql($db3, "CREATE PUBLICATION test_pub4 FOR ALL TABLES;");
+
+$node_a->wait_for_replay_catchup($node_b);
+
+# Verify the existing publications
+ok( $node_b->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_b->stop;
+
+# Run pg_createsubscriber on node A without using
+# '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_b->data_dir,
+		'--publisher-server' => $node_a->connstr($db3),
+		'--socketdir' => $node_b->host,
+		'--subscriber-port' => $node_b->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --cleanup-existing-publications on node A'
+);
+
+$node_b->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_b->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
+# Drop the newly created publications
+$node_a->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub3;");
+$node_a->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub4;");
+
 # clean up
 $node_p->teardown_node;
 $node_s->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
+$node_a->teardown_node;
+$node_b->teardown_node;
 
 done_testing();
-- 
2.34.1

From 105b1be8b65132bda38d01aa364deb6c063b0b48 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Thu, 13 Feb 2025 09:25:11 +0530
Subject: [PATCH v10] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The --cleanup-existing-publications option allows users to remove replicated
publications from the subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed.
By default, publications are preserved to avoid unintended data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   |  97 +++++++---
 .../t/040_pg_createsubscriber.pl              | 180 +++++++++++++-----
 3 files changed, 208 insertions(+), 80 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index d56487fe2c..a98b583537 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 9fdf15e5ac..d1aa39c99e 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -43,6 +43,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		drop_publications;	/* drop all publications */
 };
 
 struct LogicalRepInfo
@@ -79,7 +80,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool drop_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -97,7 +99,11 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication_by_name(PGconn *conn, const char *pubname,
+									 const char *dbname);
+static void check_and_drop_existing_publications(PGconn *conn,
+												 const char *dbname,
+												 bool drop_publications);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -180,7 +186,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfo[i]);
+					drop_publication_by_name(conn, dbinfo[i].pubname,
+											 dbinfo[i].dbname);
 				if (dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfo[i], dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -220,6 +227,8 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications\n"
+			 "                                  drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1154,10 +1163,12 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' is true, existing publications on
+ * the subscriber will be dropped before creating new subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1178,8 +1189,14 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (cleanup_existing_publications)
+			check_and_drop_existing_publications(conn, dbinfo[i].dbname,
+												 cleanup_existing_publications);
+		else
+			drop_publication_by_name(conn, dbinfo[i].pubname, dbinfo[i].dbname);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1643,25 +1660,47 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Check and drop existing publications on the subscriber if requested.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+check_and_drop_existing_publications(PGconn *conn, const char *dbname,
+									 bool drop_publications)
 {
-	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
 
-	Assert(conn != NULL);
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbname);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication_by_name(conn, PQgetvalue(res, i, 0), dbname);
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbname);
+}
 
-	PQfreemem(pubname_esc);
+/* Drop a single publication, given in dbinfo. */
+static void
+drop_publication_by_name(PGconn *conn, const char *pubname, const char *dbname)
+{
+	PQExpBuffer str = createPQExpBuffer();
+	PGresult   *res;
+
+	char	   *pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
+
+	pg_log_info("dropping publication %s in database \"%s\"", pubname, dbname);
+
+	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
 	pg_log_debug("command is: %s", str->data);
 
@@ -1670,21 +1709,16 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		res = PQexec(conn, str->data);
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
-
-			/*
-			 * Don't disconnect and exit here. This routine is used by primary
-			 * (cleanup publication / replication slot due to an error) and
-			 * subscriber (remove the replicated publications). In both cases,
-			 * it can continue and provide instructions for the user to remove
-			 * it later if cleanup fails.
-			 */
+			pg_log_error("could not drop publication %s in database \"%s\": %s",
+						 pubname, dbname, PQresultErrorMessage(res));
 		}
 		PQclear(res);
 	}
 
+	/* For cleanup purposes */
+	dbinfo->made_publication = true;
+
+	PQfreemem(pubname_esc);
 	destroyPQExpBuffer(str);
 }
 
@@ -1888,6 +1922,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1955,6 +1990,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.drop_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1972,11 +2008,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:U:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:U:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.drop_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2252,7 +2291,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfo, consistent_lsn);
+	setup_subscriber(dbinfo, consistent_lsn, opt.drop_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c8dbdb7e9b..801392b4bb 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -152,16 +152,16 @@ $node_p->safe_psql($db2,
 
 # Set up node S as standby linking to node P
 $node_p->backup('backup_1');
-my $node_s = PostgreSQL::Test::Cluster->new('node_s');
-$node_s->init_from_backup($node_p, 'backup_1', has_streaming => 1);
-$node_s->append_conf(
+my $node_s1 = PostgreSQL::Test::Cluster->new('node_s1');
+$node_s1->init_from_backup($node_p, 'backup_1', has_streaming => 1);
+$node_s1->append_conf(
 	'postgresql.conf', qq[
 primary_slot_name = '$slotname'
 primary_conninfo = '$pconnstr dbname=postgres'
 hot_standby_feedback = on
 ]);
-$node_s->set_standby_mode();
-$node_s->start;
+$node_s1->set_standby_mode();
+$node_s1->start;
 
 # Set up node T as standby linking to node P then promote it
 my $node_t = PostgreSQL::Test::Cluster->new('node_t');
@@ -192,10 +192,10 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
@@ -216,9 +216,9 @@ command_fails(
 	'subscriber data directory is not a copy of the source database cluster');
 
 # Set up node C as standby linking to node S
-$node_s->backup('backup_2');
+$node_s1->backup('backup_2');
 my $node_c = PostgreSQL::Test::Cluster->new('node_c');
-$node_c->init_from_backup($node_s, 'backup_2', has_streaming => 1);
+$node_c->init_from_backup($node_s1, 'backup_2', has_streaming => 1);
 $node_c->adjust_conf('postgresql.conf', 'primary_slot_name', undef);
 $node_c->set_standby_mode();
 
@@ -229,7 +229,7 @@ command_fails(
 		'--verbose',
 		'--dry-run',
 		'--pgdata' => $node_c->data_dir,
-		'--publisher-server' => $node_s->connstr($db1),
+		'--publisher-server' => $node_s1->connstr($db1),
 		'--socketdir' => $node_c->host,
 		'--subscriber-port' => $node_c->port,
 		'--database' => $db1,
@@ -246,16 +246,16 @@ max_wal_senders = 1
 max_worker_processes = 2
 });
 $node_p->restart;
-$node_s->stop;
+$node_s1->stop;
 command_fails(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 
@@ -272,7 +272,7 @@ max_worker_processes = 8
 });
 
 # Check some unmet conditions on node S
-$node_s->append_conf(
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 1
 max_logical_replication_workers = 1
@@ -283,15 +283,15 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
 	'standby contains unmet conditions on node S');
-$node_s->append_conf(
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 10
 max_logical_replication_workers = 4
@@ -305,12 +305,12 @@ my $fslotname = 'failover_slot';
 $node_p->safe_psql($db1,
 	"SELECT pg_create_logical_replication_slot('$fslotname', 'pgoutput', false, false, true)"
 );
-$node_s->start;
+$node_s1->start;
 # Wait for the standby to catch up so that the standby is not lagging behind
 # the failover slot.
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
-my $result = $node_s->safe_psql('postgres',
+$node_p->wait_for_replay_catchup($node_s1);
+$node_s1->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
+my $result = $node_s1->safe_psql('postgres',
 	"SELECT slot_name FROM pg_replication_slots WHERE slot_name = '$fslotname' AND synced AND NOT temporary"
 );
 is($result, 'failover_slot', 'failover slot is synced');
@@ -321,15 +321,30 @@ is($result, 'failover_slot', 'failover slot is synced');
 # slot) xmin on standby could be ahead of the remote slot leading
 # to failure in synchronization.
 $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('second row')");
-$node_p->wait_for_replay_catchup($node_s);
+$node_p->wait_for_replay_catchup($node_s1);
 
 # Create subscription to test its removal
 my $dummy_sub = 'regress_sub_dummy';
 $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->stop;
+$node_p->wait_for_replay_catchup($node_s1);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--cleanup-existing-publications'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s1);
+
+ok( $node_s1->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
+$node_s1->stop;
 
 # dry run mode on node S
 command_ok(
@@ -338,10 +353,10 @@ command_ok(
 		'--verbose',
 		'--dry-run',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--subscription' => 'sub1',
@@ -352,10 +367,10 @@ command_ok(
 	'run pg_createsubscriber --dry-run on node S');
 
 # Check if node S is still a standby
-$node_s->start;
-is($node_s->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
+$node_s1->start;
+is($node_s1->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
 	't', 'standby is in recovery');
-$node_s->stop;
+$node_s1->stop;
 
 # pg_createsubscriber can run without --databases option
 command_ok(
@@ -363,31 +378,32 @@ command_ok(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--replication-slot' => 'replslot1',
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose', '--verbose',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--replication-slot' => 'replslot1',
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -404,53 +420,115 @@ $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('third row')");
 $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 
 # Start subscriber
-$node_s->start;
+$node_s1->start;
+
+# Confirm publications are removed from the subscriber node
+is($node_s1->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
 
 # Confirm the pre-existing subscription has been removed
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT count(*) FROM pg_subscription WHERE subname = '$dummy_sub'
 ));
 is($result, qq(0), 'pre-existing subscription was dropped');
 
 # Get subscription names
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT subname FROM pg_subscription WHERE subname ~ '^pg_createsubscriber_'
 ));
 my @subnames = split("\n", $result);
 
 # Wait subscriber to catch up
-$node_s->wait_for_subscription_sync($node_p, $subnames[0]);
-$node_s->wait_for_subscription_sync($node_p, $subnames[1]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[0]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[1]);
 
 # Confirm the failover slot has been removed
-$result = $node_s->safe_psql($db1,
+$result = $node_s1->safe_psql($db1,
 	"SELECT count(*) FROM pg_replication_slots WHERE slot_name = '$fslotname'"
 );
 is($result, qq(0), 'failover slot was removed');
 
 # Check result in database $db1
-$result = $node_s->safe_psql($db1, 'SELECT * FROM tbl1');
+$result = $node_s1->safe_psql($db1, 'SELECT * FROM tbl1');
 is( $result, qq(first row
 second row
 third row),
 	"logical replication works in database $db1");
 
 # Check result in database $db2
-$result = $node_s->safe_psql($db2, 'SELECT * FROM tbl2');
+$result = $node_s1->safe_psql($db2, 'SELECT * FROM tbl2');
 is($result, qq(row 1), "logical replication works in database $db2");
 
 # Different system identifier?
 my $sysid_p = $node_p->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
-my $sysid_s = $node_s->safe_psql('postgres',
+my $sysid_s = $node_s1->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Reuse P as primary
+# Set up node S2 as standby linking to node P
+$node_p->backup('backup_3');
+my $node_s2 = PostgreSQL::Test::Cluster->new('node_s2');
+$node_s2->init_from_backup($node_p, 'backup_3', has_streaming => 1);
+$node_s2->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$pconnstr'
+       hot_standby_feedback = on
+       max_logical_replication_workers = 5
+       ]);
+$node_s2->set_standby_mode();
+$node_s2->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_p, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_p->safe_psql($db3, "CREATE PUBLICATION test_pub3 FOR ALL TABLES;");
+$node_p->safe_psql($db3, "CREATE PUBLICATION test_pub4 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s2);
+
+# Verify the existing publications
+ok( $node_s2->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_s2->stop;
+
+# Run pg_createsubscriber on node A without using
+# '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_s2->data_dir,
+		'--publisher-server' => $node_p->connstr($db3),
+		'--socketdir' => $node_s2->host,
+		'--subscriber-port' => $node_s2->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --cleanup-existing-publications on node A'
+);
+
+$node_s2->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_s2->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
+# Drop the newly created publications
+$node_p->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub3;");
+$node_p->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub4;");
+
 # clean up
 $node_p->teardown_node;
-$node_s->teardown_node;
+$node_s1->teardown_node;
+$node_s2->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
 
-- 
2.34.1

From b0456d42b3de01e227173f11b2f20e51615353f1 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Fri, 28 Feb 2025 14:44:23 +0530
Subject: [PATCH v11] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The --cleanup-existing-publications option allows users to remove replicated
publications from the subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed.
By default, publications are preserved to avoid unintended data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   |  94 ++++++---
 .../t/040_pg_createsubscriber.pl              | 187 +++++++++++++-----
 3 files changed, 209 insertions(+), 83 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..5878eef0ea0 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index a5a2d61165d..8ac8c5bbdf5 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -44,6 +44,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		drop_publications;	/* drop all publications */
 };
 
 /* per-database publication/subscription info */
@@ -91,7 +92,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool cleanup_existing_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -109,7 +111,10 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication_by_name(PGconn *conn, const char *pubname,
+									 const char *dbname);
+static void check_and_drop_existing_publications(PGconn *conn,
+												 const char *dbname);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -192,7 +197,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfos.dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfos.dbinfo[i]);
+					drop_publication_by_name(conn, dbinfos.dbinfo[i].pubname,
+											 dbinfos.dbinfo[i].dbname);
 				if (dbinfos.dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfos.dbinfo[i], dbinfos.dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -234,6 +240,8 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications\n"
+			 "                                  drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1171,10 +1179,12 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' is true, existing publications on
+ * the subscriber will be dropped before creating new subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1195,8 +1205,13 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (cleanup_existing_publications)
+			check_and_drop_existing_publications(conn, dbinfo[i].dbname);
+		else
+			drop_publication_by_name(conn, dbinfo[i].pubname, dbinfo[i].dbname);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1661,25 +1676,46 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Check and drop existing publications on the subscriber if requested.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+check_and_drop_existing_publications(PGconn *conn, const char *dbname)
 {
-	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
 
-	Assert(conn != NULL);
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbname);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication_by_name(conn, PQgetvalue(res, i, 0), dbname);
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbname);
+}
 
-	PQfreemem(pubname_esc);
+/* Drop a single publication, given in dbinfo. */
+static void
+drop_publication_by_name(PGconn *conn, const char *pubname, const char *dbname)
+{
+	PQExpBuffer str = createPQExpBuffer();
+	PGresult   *res;
+
+	char	   *pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
+
+	pg_log_info("dropping publication %s in database \"%s\"", pubname, dbname);
+
+	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
 	pg_log_debug("command is: %s", str->data);
 
@@ -1688,21 +1724,16 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		res = PQexec(conn, str->data);
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
-
-			/*
-			 * Don't disconnect and exit here. This routine is used by primary
-			 * (cleanup publication / replication slot due to an error) and
-			 * subscriber (remove the replicated publications). In both cases,
-			 * it can continue and provide instructions for the user to remove
-			 * it later if cleanup fails.
-			 */
+			pg_log_error("could not drop publication %s in database \"%s\": %s",
+						 pubname, dbname, PQresultErrorMessage(res));
 		}
 		PQclear(res);
 	}
 
+	/* For cleanup purposes */
+	dbinfos.dbinfo->made_publication = true;
+
+	PQfreemem(pubname_esc);
 	destroyPQExpBuffer(str);
 }
 
@@ -1907,6 +1938,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1976,6 +2008,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.drop_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1993,11 +2026,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.drop_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2278,7 +2314,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfos.dbinfo, consistent_lsn);
+	setup_subscriber(dbinfos.dbinfo, consistent_lsn, opt.drop_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfos.dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..d2e46bee9c4 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -152,16 +152,16 @@ $node_p->safe_psql($db2,
 
 # Set up node S as standby linking to node P
 $node_p->backup('backup_1');
-my $node_s = PostgreSQL::Test::Cluster->new('node_s');
-$node_s->init_from_backup($node_p, 'backup_1', has_streaming => 1);
-$node_s->append_conf(
+my $node_s1 = PostgreSQL::Test::Cluster->new('node_s1');
+$node_s1->init_from_backup($node_p, 'backup_1', has_streaming => 1);
+$node_s1->append_conf(
 	'postgresql.conf', qq[
 primary_slot_name = '$slotname'
 primary_conninfo = '$pconnstr dbname=postgres'
 hot_standby_feedback = on
 ]);
-$node_s->set_standby_mode();
-$node_s->start;
+$node_s1->set_standby_mode();
+$node_s1->start;
 
 # Set up node T as standby linking to node P then promote it
 my $node_t = PostgreSQL::Test::Cluster->new('node_t');
@@ -192,10 +192,10 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
@@ -216,9 +216,9 @@ command_fails(
 	'subscriber data directory is not a copy of the source database cluster');
 
 # Set up node C as standby linking to node S
-$node_s->backup('backup_2');
+$node_s1->backup('backup_2');
 my $node_c = PostgreSQL::Test::Cluster->new('node_c');
-$node_c->init_from_backup($node_s, 'backup_2', has_streaming => 1);
+$node_c->init_from_backup($node_s1, 'backup_2', has_streaming => 1);
 $node_c->adjust_conf('postgresql.conf', 'primary_slot_name', undef);
 $node_c->set_standby_mode();
 
@@ -229,7 +229,7 @@ command_fails(
 		'--verbose',
 		'--dry-run',
 		'--pgdata' => $node_c->data_dir,
-		'--publisher-server' => $node_s->connstr($db1),
+		'--publisher-server' => $node_s1->connstr($db1),
 		'--socketdir' => $node_c->host,
 		'--subscriber-port' => $node_c->port,
 		'--database' => $db1,
@@ -246,16 +246,16 @@ max_wal_senders = 1
 max_worker_processes = 2
 });
 $node_p->restart;
-$node_s->stop;
+$node_s1->stop;
 command_fails(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 
@@ -272,7 +272,7 @@ max_worker_processes = 8
 });
 
 # Check some unmet conditions on node S
-$node_s->append_conf(
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 1
 max_logical_replication_workers = 1
@@ -283,15 +283,15 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
 	'standby contains unmet conditions on node S');
-$node_s->append_conf(
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 10
 max_logical_replication_workers = 4
@@ -305,12 +305,12 @@ my $fslotname = 'failover_slot';
 $node_p->safe_psql($db1,
 	"SELECT pg_create_logical_replication_slot('$fslotname', 'pgoutput', false, false, true)"
 );
-$node_s->start;
+$node_s1->start;
 # Wait for the standby to catch up so that the standby is not lagging behind
 # the failover slot.
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
-my $result = $node_s->safe_psql('postgres',
+$node_p->wait_for_replay_catchup($node_s1);
+$node_s1->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
+my $result = $node_s1->safe_psql('postgres',
 	"SELECT slot_name FROM pg_replication_slots WHERE slot_name = '$fslotname' AND synced AND NOT temporary"
 );
 is($result, 'failover_slot', 'failover slot is synced');
@@ -321,15 +321,30 @@ is($result, 'failover_slot', 'failover slot is synced');
 # slot) xmin on standby could be ahead of the remote slot leading
 # to failure in synchronization.
 $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('second row')");
-$node_p->wait_for_replay_catchup($node_s);
+$node_p->wait_for_replay_catchup($node_s1);
 
 # Create subscription to test its removal
 my $dummy_sub = 'regress_sub_dummy';
 $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->stop;
+$node_p->wait_for_replay_catchup($node_s1);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--cleanup-existing-publications'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s1);
+
+ok( $node_s1->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
+$node_s1->stop;
 
 # dry run mode on node S
 command_ok(
@@ -338,10 +353,10 @@ command_ok(
 		'--verbose',
 		'--dry-run',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--subscription' => 'sub1',
@@ -352,10 +367,11 @@ command_ok(
 	'run pg_createsubscriber --dry-run on node S');
 
 # Check if node S is still a standby
-$node_s->start;
-is($node_s->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
-	't', 'standby is in recovery');
-$node_s->stop;
+$node_s1->start;
+is( $node_s1->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
+	't',
+	'standby is in recovery');
+$node_s1->stop;
 
 # pg_createsubscriber can run without --databases option
 command_ok(
@@ -363,33 +379,34 @@ command_ok(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--replication-slot' => 'replslot1',
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
 # In passing, also test the --enable-two-phase option
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose', '--verbose',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--replication-slot' => 'replslot1',
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,11 +423,16 @@ $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('third row')");
 $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 
 # Start subscriber
-$node_s->start;
+$node_s1->start;
+
+# Confirm publications are removed from the subscriber node
+is($node_s1->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
 
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
-is( $node_s->safe_psql(
+is( $node_s1->safe_psql(
 		'postgres',
 		"SELECT count(1) = 0 FROM pg_subscription WHERE subtwophasestate = 'd'"
 	),
@@ -418,50 +440,107 @@ is( $node_s->safe_psql(
 	'subscriptions are created with the two-phase option enabled');
 
 # Confirm the pre-existing subscription has been removed
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT count(*) FROM pg_subscription WHERE subname = '$dummy_sub'
 ));
 is($result, qq(0), 'pre-existing subscription was dropped');
 
 # Get subscription names
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT subname FROM pg_subscription WHERE subname ~ '^pg_createsubscriber_'
 ));
 my @subnames = split("\n", $result);
 
 # Wait subscriber to catch up
-$node_s->wait_for_subscription_sync($node_p, $subnames[0]);
-$node_s->wait_for_subscription_sync($node_p, $subnames[1]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[0]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[1]);
 
 # Confirm the failover slot has been removed
-$result = $node_s->safe_psql($db1,
+$result = $node_s1->safe_psql($db1,
 	"SELECT count(*) FROM pg_replication_slots WHERE slot_name = '$fslotname'"
 );
 is($result, qq(0), 'failover slot was removed');
 
 # Check result in database $db1
-$result = $node_s->safe_psql($db1, 'SELECT * FROM tbl1');
+$result = $node_s1->safe_psql($db1, 'SELECT * FROM tbl1');
 is( $result, qq(first row
 second row
 third row),
 	"logical replication works in database $db1");
 
 # Check result in database $db2
-$result = $node_s->safe_psql($db2, 'SELECT * FROM tbl2');
+$result = $node_s1->safe_psql($db2, 'SELECT * FROM tbl2');
 is($result, qq(row 1), "logical replication works in database $db2");
 
 # Different system identifier?
 my $sysid_p = $node_p->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
-my $sysid_s = $node_s->safe_psql('postgres',
+my $sysid_s = $node_s1->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Reuse P as primary
+# Set up node S2 as standby linking to node P
+$node_p->backup('backup_3');
+my $node_s2 = PostgreSQL::Test::Cluster->new('node_s2');
+$node_s2->init_from_backup($node_p, 'backup_3', has_streaming => 1);
+$node_s2->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$pconnstr'
+       hot_standby_feedback = on
+       max_logical_replication_workers = 5
+       ]);
+$node_s2->set_standby_mode();
+$node_s2->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_p, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_p->safe_psql($db3, "CREATE PUBLICATION test_pub3 FOR ALL TABLES;");
+$node_p->safe_psql($db3, "CREATE PUBLICATION test_pub4 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s2);
+
+# Verify the existing publications
+ok( $node_s2->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_s2->stop;
+
+# Run pg_createsubscriber on node A without using
+# '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_s2->data_dir,
+		'--publisher-server' => $node_p->connstr($db3),
+		'--socketdir' => $node_s2->host,
+		'--subscriber-port' => $node_s2->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --cleanup-existing-publications on node A'
+);
+
+$node_s2->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_s2->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
+# Drop the newly created publications
+$node_p->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub3;");
+$node_p->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub4;");
+
 # clean up
 $node_p->teardown_node;
-$node_s->teardown_node;
+$node_s1->teardown_node;
+$node_s2->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
 
-- 
2.34.1

From 7c26a757be642977a6db7e8d4255912ca5aaae42 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Fri, 28 Feb 2025 14:44:23 +0530
Subject: [PATCH v12] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The --cleanup-existing-publications option allows users to remove replicated
publications from the subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed.
By default, publications are preserved to avoid unintended data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   |  84 ++++++--
 .../t/040_pg_createsubscriber.pl              | 187 +++++++++++++-----
 3 files changed, 207 insertions(+), 75 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..5878eef0ea0 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index a5a2d61165d..37aa7e8a608 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -44,6 +44,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		drop_publications;	/* drop all publications */
 };
 
 /* per-database publication/subscription info */
@@ -91,7 +92,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool cleanup_existing_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -109,7 +111,10 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication_by_name(PGconn *conn, const char *pubname,
+									 const char *dbname);
+static void check_and_drop_existing_publications(PGconn *conn,
+												 const char *dbname);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -192,7 +197,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfos.dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfos.dbinfo[i]);
+					drop_publication_by_name(conn, dbinfos.dbinfo[i].pubname,
+											 dbinfos.dbinfo[i].dbname);
 				if (dbinfos.dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfos.dbinfo[i], dbinfos.dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -234,6 +240,8 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications\n"
+			 "                                  drop all publications on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1171,10 +1179,12 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' is true, existing publications on
+ * the subscriber will be dropped before creating new subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1195,8 +1205,13 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * Since the publication was created before the consistent LSN, it is
 		 * available on the subscriber when the physical replica is promoted.
 		 * Remove publications from the subscriber because it has no use.
+		 * Additionally, drop publications existed before this command if
+		 * requested.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (cleanup_existing_publications)
+			check_and_drop_existing_publications(conn, dbinfo[i].dbname);
+		else
+			drop_publication_by_name(conn, dbinfo[i].pubname, dbinfo[i].dbname);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1661,25 +1676,46 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Check and drop existing publications on the subscriber if requested.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+check_and_drop_existing_publications(PGconn *conn, const char *dbname)
 {
-	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
 
-	Assert(conn != NULL);
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbname);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication_by_name(conn, PQgetvalue(res, i, 0), dbname);
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbname);
+}
 
-	PQfreemem(pubname_esc);
+/* Drop a single publication, given in dbinfo. */
+static void
+drop_publication_by_name(PGconn *conn, const char *pubname, const char *dbname)
+{
+	PQExpBuffer str = createPQExpBuffer();
+	PGresult   *res;
+
+	char	   *pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
+
+	pg_log_info("dropping publication %s in database \"%s\"", pubname, dbname);
+
+	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
 	pg_log_debug("command is: %s", str->data);
 
@@ -1688,9 +1724,9 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		res = PQexec(conn, str->data);
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
-			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+			pg_log_error("could not drop publication %s in database \"%s\": %s",
+						 pubname, dbname, PQresultErrorMessage(res));
+			dbinfos.dbinfo->made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1703,6 +1739,7 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		PQclear(res);
 	}
 
+	PQfreemem(pubname_esc);
 	destroyPQExpBuffer(str);
 }
 
@@ -1907,6 +1944,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1976,6 +2014,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.drop_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1993,11 +2032,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.drop_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2278,7 +2320,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfos.dbinfo, consistent_lsn);
+	setup_subscriber(dbinfos.dbinfo, consistent_lsn, opt.drop_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfos.dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..d2e46bee9c4 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -152,16 +152,16 @@ $node_p->safe_psql($db2,
 
 # Set up node S as standby linking to node P
 $node_p->backup('backup_1');
-my $node_s = PostgreSQL::Test::Cluster->new('node_s');
-$node_s->init_from_backup($node_p, 'backup_1', has_streaming => 1);
-$node_s->append_conf(
+my $node_s1 = PostgreSQL::Test::Cluster->new('node_s1');
+$node_s1->init_from_backup($node_p, 'backup_1', has_streaming => 1);
+$node_s1->append_conf(
 	'postgresql.conf', qq[
 primary_slot_name = '$slotname'
 primary_conninfo = '$pconnstr dbname=postgres'
 hot_standby_feedback = on
 ]);
-$node_s->set_standby_mode();
-$node_s->start;
+$node_s1->set_standby_mode();
+$node_s1->start;
 
 # Set up node T as standby linking to node P then promote it
 my $node_t = PostgreSQL::Test::Cluster->new('node_t');
@@ -192,10 +192,10 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
@@ -216,9 +216,9 @@ command_fails(
 	'subscriber data directory is not a copy of the source database cluster');
 
 # Set up node C as standby linking to node S
-$node_s->backup('backup_2');
+$node_s1->backup('backup_2');
 my $node_c = PostgreSQL::Test::Cluster->new('node_c');
-$node_c->init_from_backup($node_s, 'backup_2', has_streaming => 1);
+$node_c->init_from_backup($node_s1, 'backup_2', has_streaming => 1);
 $node_c->adjust_conf('postgresql.conf', 'primary_slot_name', undef);
 $node_c->set_standby_mode();
 
@@ -229,7 +229,7 @@ command_fails(
 		'--verbose',
 		'--dry-run',
 		'--pgdata' => $node_c->data_dir,
-		'--publisher-server' => $node_s->connstr($db1),
+		'--publisher-server' => $node_s1->connstr($db1),
 		'--socketdir' => $node_c->host,
 		'--subscriber-port' => $node_c->port,
 		'--database' => $db1,
@@ -246,16 +246,16 @@ max_wal_senders = 1
 max_worker_processes = 2
 });
 $node_p->restart;
-$node_s->stop;
+$node_s1->stop;
 command_fails(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 
@@ -272,7 +272,7 @@ max_worker_processes = 8
 });
 
 # Check some unmet conditions on node S
-$node_s->append_conf(
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 1
 max_logical_replication_workers = 1
@@ -283,15 +283,15 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
 	'standby contains unmet conditions on node S');
-$node_s->append_conf(
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 10
 max_logical_replication_workers = 4
@@ -305,12 +305,12 @@ my $fslotname = 'failover_slot';
 $node_p->safe_psql($db1,
 	"SELECT pg_create_logical_replication_slot('$fslotname', 'pgoutput', false, false, true)"
 );
-$node_s->start;
+$node_s1->start;
 # Wait for the standby to catch up so that the standby is not lagging behind
 # the failover slot.
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
-my $result = $node_s->safe_psql('postgres',
+$node_p->wait_for_replay_catchup($node_s1);
+$node_s1->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
+my $result = $node_s1->safe_psql('postgres',
 	"SELECT slot_name FROM pg_replication_slots WHERE slot_name = '$fslotname' AND synced AND NOT temporary"
 );
 is($result, 'failover_slot', 'failover slot is synced');
@@ -321,15 +321,30 @@ is($result, 'failover_slot', 'failover slot is synced');
 # slot) xmin on standby could be ahead of the remote slot leading
 # to failure in synchronization.
 $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('second row')");
-$node_p->wait_for_replay_catchup($node_s);
+$node_p->wait_for_replay_catchup($node_s1);
 
 # Create subscription to test its removal
 my $dummy_sub = 'regress_sub_dummy';
 $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->stop;
+$node_p->wait_for_replay_catchup($node_s1);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--cleanup-existing-publications'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s1);
+
+ok( $node_s1->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
+$node_s1->stop;
 
 # dry run mode on node S
 command_ok(
@@ -338,10 +353,10 @@ command_ok(
 		'--verbose',
 		'--dry-run',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--subscription' => 'sub1',
@@ -352,10 +367,11 @@ command_ok(
 	'run pg_createsubscriber --dry-run on node S');
 
 # Check if node S is still a standby
-$node_s->start;
-is($node_s->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
-	't', 'standby is in recovery');
-$node_s->stop;
+$node_s1->start;
+is( $node_s1->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
+	't',
+	'standby is in recovery');
+$node_s1->stop;
 
 # pg_createsubscriber can run without --databases option
 command_ok(
@@ -363,33 +379,34 @@ command_ok(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--replication-slot' => 'replslot1',
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
 # In passing, also test the --enable-two-phase option
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose', '--verbose',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--replication-slot' => 'replslot1',
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,11 +423,16 @@ $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('third row')");
 $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 
 # Start subscriber
-$node_s->start;
+$node_s1->start;
+
+# Confirm publications are removed from the subscriber node
+is($node_s1->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
 
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
-is( $node_s->safe_psql(
+is( $node_s1->safe_psql(
 		'postgres',
 		"SELECT count(1) = 0 FROM pg_subscription WHERE subtwophasestate = 'd'"
 	),
@@ -418,50 +440,107 @@ is( $node_s->safe_psql(
 	'subscriptions are created with the two-phase option enabled');
 
 # Confirm the pre-existing subscription has been removed
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT count(*) FROM pg_subscription WHERE subname = '$dummy_sub'
 ));
 is($result, qq(0), 'pre-existing subscription was dropped');
 
 # Get subscription names
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT subname FROM pg_subscription WHERE subname ~ '^pg_createsubscriber_'
 ));
 my @subnames = split("\n", $result);
 
 # Wait subscriber to catch up
-$node_s->wait_for_subscription_sync($node_p, $subnames[0]);
-$node_s->wait_for_subscription_sync($node_p, $subnames[1]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[0]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[1]);
 
 # Confirm the failover slot has been removed
-$result = $node_s->safe_psql($db1,
+$result = $node_s1->safe_psql($db1,
 	"SELECT count(*) FROM pg_replication_slots WHERE slot_name = '$fslotname'"
 );
 is($result, qq(0), 'failover slot was removed');
 
 # Check result in database $db1
-$result = $node_s->safe_psql($db1, 'SELECT * FROM tbl1');
+$result = $node_s1->safe_psql($db1, 'SELECT * FROM tbl1');
 is( $result, qq(first row
 second row
 third row),
 	"logical replication works in database $db1");
 
 # Check result in database $db2
-$result = $node_s->safe_psql($db2, 'SELECT * FROM tbl2');
+$result = $node_s1->safe_psql($db2, 'SELECT * FROM tbl2');
 is($result, qq(row 1), "logical replication works in database $db2");
 
 # Different system identifier?
 my $sysid_p = $node_p->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
-my $sysid_s = $node_s->safe_psql('postgres',
+my $sysid_s = $node_s1->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Reuse P as primary
+# Set up node S2 as standby linking to node P
+$node_p->backup('backup_3');
+my $node_s2 = PostgreSQL::Test::Cluster->new('node_s2');
+$node_s2->init_from_backup($node_p, 'backup_3', has_streaming => 1);
+$node_s2->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$pconnstr'
+       hot_standby_feedback = on
+       max_logical_replication_workers = 5
+       ]);
+$node_s2->set_standby_mode();
+$node_s2->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_p, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_p->safe_psql($db3, "CREATE PUBLICATION test_pub3 FOR ALL TABLES;");
+$node_p->safe_psql($db3, "CREATE PUBLICATION test_pub4 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s2);
+
+# Verify the existing publications
+ok( $node_s2->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_s2->stop;
+
+# Run pg_createsubscriber on node A without using
+# '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_s2->data_dir,
+		'--publisher-server' => $node_p->connstr($db3),
+		'--socketdir' => $node_s2->host,
+		'--subscriber-port' => $node_s2->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --cleanup-existing-publications on node A'
+);
+
+$node_s2->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_s2->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
+# Drop the newly created publications
+$node_p->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub3;");
+$node_p->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub4;");
+
 # clean up
 $node_p->teardown_node;
-$node_s->teardown_node;
+$node_s1->teardown_node;
+$node_s2->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
 
-- 
2.41.0.windows.3

From fea696fb4bbac7dd42c0867b3b020e2317cb4db1 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Fri, 28 Feb 2025 14:44:23 +0530
Subject: [PATCH v13] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--cleanup-existing-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The --cleanup-existing-publications option allows users to remove replicated
publications from the subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed.
By default, publications are preserved to avoid unintended data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 ++
 src/bin/pg_basebackup/pg_createsubscriber.c   |  89 ++++++---
 .../t/040_pg_createsubscriber.pl              | 187 +++++++++++++-----
 3 files changed, 210 insertions(+), 77 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..5878eef0ea0 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--cleanup-existing-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index a5a2d61165d..3b498d5047e 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -44,6 +44,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		drop_publications;	/* drop all publications */
 };
 
 /* per-database publication/subscription info */
@@ -91,7 +92,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool cleanup_existing_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -109,7 +111,10 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication_by_name(PGconn *conn, const char *pubname,
+									 const char *dbname);
+static void check_and_drop_existing_publications(PGconn *conn,
+												 const char *dbname);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -192,7 +197,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfos.dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfos.dbinfo[i]);
+					drop_publication_by_name(conn, dbinfos.dbinfo[i].pubname,
+											 dbinfos.dbinfo[i].dbname);
 				if (dbinfos.dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfos.dbinfo[i], dbinfos.dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -234,6 +240,8 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --cleanup-existing-publications\n"
+			 "                                  drop all publications from specified subscriber databases\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1171,10 +1179,13 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' options is true, existing
+ * publications on the subscriber will be dropped before creating new
+ * subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool cleanup_existing_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1192,11 +1203,16 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publication was created before the consistent LSN, it
+		 * remains on the subscriber even after the physical replica is
+		 * promoted. Remove this publication from the subscriber because it
+		 * has no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (cleanup_existing_publications)
+			check_and_drop_existing_publications(conn, dbinfo[i].dbname);
+		else
+			drop_publication_by_name(conn, dbinfo[i].pubname, dbinfo[i].dbname);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1661,25 +1677,46 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Check and drop existing publications on the subscriber if requested.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+check_and_drop_existing_publications(PGconn *conn, const char *dbname)
 {
-	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
 
-	Assert(conn != NULL);
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbname);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication_by_name(conn, PQgetvalue(res, i, 0), dbname);
 
-	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbname);
+}
 
-	PQfreemem(pubname_esc);
+/* Drop the specified publication of the given database. */
+static void
+drop_publication_by_name(PGconn *conn, const char *pubname, const char *dbname)
+{
+	PQExpBuffer str = createPQExpBuffer();
+	PGresult   *res;
+
+	char	   *pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
+
+	pg_log_info("dropping publication \"%s\" in database \"%s\"", pubname, dbname);
+
+	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
 	pg_log_debug("command is: %s", str->data);
 
@@ -1689,8 +1726,8 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbname, PQresultErrorMessage(res));
+			dbinfos.dbinfo->made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1703,6 +1740,7 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		PQclear(res);
 	}
 
+	PQfreemem(pubname_esc);
 	destroyPQExpBuffer(str);
 }
 
@@ -1907,6 +1945,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"cleanup-existing-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1976,6 +2015,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.drop_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1993,11 +2033,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.drop_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2278,7 +2321,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfos.dbinfo, consistent_lsn);
+	setup_subscriber(dbinfos.dbinfo, consistent_lsn, opt.drop_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfos.dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..d2e46bee9c4 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -152,16 +152,16 @@ $node_p->safe_psql($db2,
 
 # Set up node S as standby linking to node P
 $node_p->backup('backup_1');
-my $node_s = PostgreSQL::Test::Cluster->new('node_s');
-$node_s->init_from_backup($node_p, 'backup_1', has_streaming => 1);
-$node_s->append_conf(
+my $node_s1 = PostgreSQL::Test::Cluster->new('node_s1');
+$node_s1->init_from_backup($node_p, 'backup_1', has_streaming => 1);
+$node_s1->append_conf(
 	'postgresql.conf', qq[
 primary_slot_name = '$slotname'
 primary_conninfo = '$pconnstr dbname=postgres'
 hot_standby_feedback = on
 ]);
-$node_s->set_standby_mode();
-$node_s->start;
+$node_s1->set_standby_mode();
+$node_s1->start;
 
 # Set up node T as standby linking to node P then promote it
 my $node_t = PostgreSQL::Test::Cluster->new('node_t');
@@ -192,10 +192,10 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
@@ -216,9 +216,9 @@ command_fails(
 	'subscriber data directory is not a copy of the source database cluster');
 
 # Set up node C as standby linking to node S
-$node_s->backup('backup_2');
+$node_s1->backup('backup_2');
 my $node_c = PostgreSQL::Test::Cluster->new('node_c');
-$node_c->init_from_backup($node_s, 'backup_2', has_streaming => 1);
+$node_c->init_from_backup($node_s1, 'backup_2', has_streaming => 1);
 $node_c->adjust_conf('postgresql.conf', 'primary_slot_name', undef);
 $node_c->set_standby_mode();
 
@@ -229,7 +229,7 @@ command_fails(
 		'--verbose',
 		'--dry-run',
 		'--pgdata' => $node_c->data_dir,
-		'--publisher-server' => $node_s->connstr($db1),
+		'--publisher-server' => $node_s1->connstr($db1),
 		'--socketdir' => $node_c->host,
 		'--subscriber-port' => $node_c->port,
 		'--database' => $db1,
@@ -246,16 +246,16 @@ max_wal_senders = 1
 max_worker_processes = 2
 });
 $node_p->restart;
-$node_s->stop;
+$node_s1->stop;
 command_fails(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 
@@ -272,7 +272,7 @@ max_worker_processes = 8
 });
 
 # Check some unmet conditions on node S
-$node_s->append_conf(
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 1
 max_logical_replication_workers = 1
@@ -283,15 +283,15 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
 	'standby contains unmet conditions on node S');
-$node_s->append_conf(
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 10
 max_logical_replication_workers = 4
@@ -305,12 +305,12 @@ my $fslotname = 'failover_slot';
 $node_p->safe_psql($db1,
 	"SELECT pg_create_logical_replication_slot('$fslotname', 'pgoutput', false, false, true)"
 );
-$node_s->start;
+$node_s1->start;
 # Wait for the standby to catch up so that the standby is not lagging behind
 # the failover slot.
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
-my $result = $node_s->safe_psql('postgres',
+$node_p->wait_for_replay_catchup($node_s1);
+$node_s1->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
+my $result = $node_s1->safe_psql('postgres',
 	"SELECT slot_name FROM pg_replication_slots WHERE slot_name = '$fslotname' AND synced AND NOT temporary"
 );
 is($result, 'failover_slot', 'failover slot is synced');
@@ -321,15 +321,30 @@ is($result, 'failover_slot', 'failover slot is synced');
 # slot) xmin on standby could be ahead of the remote slot leading
 # to failure in synchronization.
 $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('second row')");
-$node_p->wait_for_replay_catchup($node_s);
+$node_p->wait_for_replay_catchup($node_s1);
 
 # Create subscription to test its removal
 my $dummy_sub = 'regress_sub_dummy';
 $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->stop;
+$node_p->wait_for_replay_catchup($node_s1);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--cleanup-existing-publications'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s1);
+
+ok( $node_s1->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --cleanup-existing-publications is run');
+
+$node_s1->stop;
 
 # dry run mode on node S
 command_ok(
@@ -338,10 +353,10 @@ command_ok(
 		'--verbose',
 		'--dry-run',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--subscription' => 'sub1',
@@ -352,10 +367,11 @@ command_ok(
 	'run pg_createsubscriber --dry-run on node S');
 
 # Check if node S is still a standby
-$node_s->start;
-is($node_s->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
-	't', 'standby is in recovery');
-$node_s->stop;
+$node_s1->start;
+is( $node_s1->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
+	't',
+	'standby is in recovery');
+$node_s1->stop;
 
 # pg_createsubscriber can run without --databases option
 command_ok(
@@ -363,33 +379,34 @@ command_ok(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--replication-slot' => 'replslot1',
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
-# to show more information.
+# Run pg_createsubscriber on node S using '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
 # In passing, also test the --enable-two-phase option
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose', '--verbose',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--replication-slot' => 'replslot1',
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--cleanup-existing-publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -406,11 +423,16 @@ $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('third row')");
 $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 
 # Start subscriber
-$node_s->start;
+$node_s1->start;
+
+# Confirm publications are removed from the subscriber node
+is($node_s1->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0',
+	'all publications dropped after --cleanup-existing-publications is run');
 
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
-is( $node_s->safe_psql(
+is( $node_s1->safe_psql(
 		'postgres',
 		"SELECT count(1) = 0 FROM pg_subscription WHERE subtwophasestate = 'd'"
 	),
@@ -418,50 +440,107 @@ is( $node_s->safe_psql(
 	'subscriptions are created with the two-phase option enabled');
 
 # Confirm the pre-existing subscription has been removed
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT count(*) FROM pg_subscription WHERE subname = '$dummy_sub'
 ));
 is($result, qq(0), 'pre-existing subscription was dropped');
 
 # Get subscription names
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT subname FROM pg_subscription WHERE subname ~ '^pg_createsubscriber_'
 ));
 my @subnames = split("\n", $result);
 
 # Wait subscriber to catch up
-$node_s->wait_for_subscription_sync($node_p, $subnames[0]);
-$node_s->wait_for_subscription_sync($node_p, $subnames[1]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[0]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[1]);
 
 # Confirm the failover slot has been removed
-$result = $node_s->safe_psql($db1,
+$result = $node_s1->safe_psql($db1,
 	"SELECT count(*) FROM pg_replication_slots WHERE slot_name = '$fslotname'"
 );
 is($result, qq(0), 'failover slot was removed');
 
 # Check result in database $db1
-$result = $node_s->safe_psql($db1, 'SELECT * FROM tbl1');
+$result = $node_s1->safe_psql($db1, 'SELECT * FROM tbl1');
 is( $result, qq(first row
 second row
 third row),
 	"logical replication works in database $db1");
 
 # Check result in database $db2
-$result = $node_s->safe_psql($db2, 'SELECT * FROM tbl2');
+$result = $node_s1->safe_psql($db2, 'SELECT * FROM tbl2');
 is($result, qq(row 1), "logical replication works in database $db2");
 
 # Different system identifier?
 my $sysid_p = $node_p->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
-my $sysid_s = $node_s->safe_psql('postgres',
+my $sysid_s = $node_s1->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Reuse P as primary
+# Set up node S2 as standby linking to node P
+$node_p->backup('backup_3');
+my $node_s2 = PostgreSQL::Test::Cluster->new('node_s2');
+$node_s2->init_from_backup($node_p, 'backup_3', has_streaming => 1);
+$node_s2->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$pconnstr'
+       hot_standby_feedback = on
+       max_logical_replication_workers = 5
+       ]);
+$node_s2->set_standby_mode();
+$node_s2->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_p, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_p->safe_psql($db3, "CREATE PUBLICATION test_pub3 FOR ALL TABLES;");
+$node_p->safe_psql($db3, "CREATE PUBLICATION test_pub4 FOR ALL TABLES;");
+
+$node_p->wait_for_replay_catchup($node_s2);
+
+# Verify the existing publications
+ok( $node_s2->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_s2->stop;
+
+# Run pg_createsubscriber on node A without using
+# '--cleanup-existing-publications'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_s2->data_dir,
+		'--publisher-server' => $node_p->connstr($db3),
+		'--socketdir' => $node_s2->host,
+		'--subscriber-port' => $node_s2->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --cleanup-existing-publications on node A'
+);
+
+$node_s2->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_s2->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
+# Drop the newly created publications
+$node_p->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub3;");
+$node_p->safe_psql($db3, "DROP PUBLICATION IF EXISTS test_pub4;");
+
 # clean up
 $node_p->teardown_node;
-$node_s->teardown_node;
+$node_s1->teardown_node;
+$node_s2->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
 
-- 
2.34.1

From 48e8be4a1f2c9fd1c103f37246eb771bb794354a Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Fri, 28 Feb 2025 14:44:23 +0530
Subject: [PATCH v14] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--drop-all-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The '--drop-all-publications' option allows users to remove replicated
publications from the subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed. By default, publications are preserved to avoid unintended
data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 +
 src/bin/pg_basebackup/pg_createsubscriber.c   |  92 ++++++--
 .../t/040_pg_createsubscriber.pl              | 201 ++++++++++++------
 3 files changed, 218 insertions(+), 86 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..80eb0e79629 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--drop-all-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index a5a2d61165d..6098e70c8db 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -44,6 +44,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		drop_publications;	/* drop all publications */
 };
 
 /* per-database publication/subscription info */
@@ -91,7 +92,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool drop_all_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -109,7 +111,10 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication_by_name(PGconn *conn, const char *dbname,
+									 const char *pubname);
+static void check_and_drop_existing_publications(PGconn *conn,
+												 const char *dbname);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -192,7 +197,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfos.dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfos.dbinfo[i]);
+					drop_publication_by_name(conn, dbinfos.dbinfo[i].dbname,
+											 dbinfos.dbinfo[i].pubname);
 				if (dbinfos.dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfos.dbinfo[i], dbinfos.dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -234,6 +240,9 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --drop-all-publications\n"
+			 "                                  drop all publications from specified databases\n"
+			 "                                  on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1171,10 +1180,13 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' parameter is true, existing
+ * publications on the subscriber will be dropped before creating new
+ * subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool drop_all_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1192,11 +1204,16 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publication was created before the consistent LSN, it
+		 * remains on the subscriber even after the physical replica is
+		 * promoted. Remove this publication from the subscriber because it
+		 * has no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (drop_all_publications)
+			check_and_drop_existing_publications(conn, dbinfo[i].dbname);
+		else
+			drop_publication_by_name(conn, dbinfo[i].dbname, dbinfo[i].pubname);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1661,26 +1678,20 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication of the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication_by_name(PGconn *conn, const char *dbname, const char *pubname)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
-
-	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	char	   *pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
-	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+	pg_log_info("dropping publication \"%s\" in database \"%s\"", pubname, dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
-	PQfreemem(pubname_esc);
-
 	pg_log_debug("command is: %s", str->data);
 
 	if (!dry_run)
@@ -1689,8 +1700,8 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbname, PQresultErrorMessage(res));
+			dbinfos.dbinfo->made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1703,9 +1714,39 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		PQclear(res);
 	}
 
+	PQfreemem(pubname_esc);
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Check and drop existing publications on the subscriber.
+ */
+static void
+check_and_drop_existing_publications(PGconn *conn, const char *dbname)
+{
+	PGresult   *res;
+
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbname);
+
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
+
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication_by_name(conn, dbname, PQgetvalue(res, i, 0));
+
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbname);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1907,6 +1948,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"drop-all-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1976,6 +2018,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.drop_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1993,11 +2036,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.drop_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2278,7 +2324,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfos.dbinfo, consistent_lsn);
+	setup_subscriber(dbinfos.dbinfo, consistent_lsn, opt.drop_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfos.dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..22db6a44971 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -150,18 +150,18 @@ my $slotname = 'physical_slot';
 $node_p->safe_psql($db2,
 	"SELECT pg_create_physical_replication_slot('$slotname')");
 
-# Set up node S as standby linking to node P
+# Set up node S1 as standby linking to node P
 $node_p->backup('backup_1');
-my $node_s = PostgreSQL::Test::Cluster->new('node_s');
-$node_s->init_from_backup($node_p, 'backup_1', has_streaming => 1);
-$node_s->append_conf(
+my $node_s1 = PostgreSQL::Test::Cluster->new('node_s1');
+$node_s1->init_from_backup($node_p, 'backup_1', has_streaming => 1);
+$node_s1->append_conf(
 	'postgresql.conf', qq[
 primary_slot_name = '$slotname'
 primary_conninfo = '$pconnstr dbname=postgres'
 hot_standby_feedback = on
 ]);
-$node_s->set_standby_mode();
-$node_s->start;
+$node_s1->set_standby_mode();
+$node_s1->start;
 
 # Set up node T as standby linking to node P then promote it
 my $node_t = PostgreSQL::Test::Cluster->new('node_t');
@@ -192,10 +192,10 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
@@ -215,10 +215,10 @@ command_fails(
 	],
 	'subscriber data directory is not a copy of the source database cluster');
 
-# Set up node C as standby linking to node S
-$node_s->backup('backup_2');
+# Set up node C as standby linking to node S1
+$node_s1->backup('backup_2');
 my $node_c = PostgreSQL::Test::Cluster->new('node_c');
-$node_c->init_from_backup($node_s, 'backup_2', has_streaming => 1);
+$node_c->init_from_backup($node_s1, 'backup_2', has_streaming => 1);
 $node_c->adjust_conf('postgresql.conf', 'primary_slot_name', undef);
 $node_c->set_standby_mode();
 
@@ -229,7 +229,7 @@ command_fails(
 		'--verbose',
 		'--dry-run',
 		'--pgdata' => $node_c->data_dir,
-		'--publisher-server' => $node_s->connstr($db1),
+		'--publisher-server' => $node_s1->connstr($db1),
 		'--socketdir' => $node_c->host,
 		'--subscriber-port' => $node_c->port,
 		'--database' => $db1,
@@ -246,16 +246,16 @@ max_wal_senders = 1
 max_worker_processes = 2
 });
 $node_p->restart;
-$node_s->stop;
+$node_s1->stop;
 command_fails(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 
@@ -271,8 +271,8 @@ max_wal_senders = 10
 max_worker_processes = 8
 });
 
-# Check some unmet conditions on node S
-$node_s->append_conf(
+# Check some unmet conditions on node S1
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 1
 max_logical_replication_workers = 1
@@ -283,15 +283,15 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
-	'standby contains unmet conditions on node S');
-$node_s->append_conf(
+	'standby contains unmet conditions on node S1');
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 10
 max_logical_replication_workers = 4
@@ -305,43 +305,58 @@ my $fslotname = 'failover_slot';
 $node_p->safe_psql($db1,
 	"SELECT pg_create_logical_replication_slot('$fslotname', 'pgoutput', false, false, true)"
 );
-$node_s->start;
+$node_s1->start;
 # Wait for the standby to catch up so that the standby is not lagging behind
 # the failover slot.
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
-my $result = $node_s->safe_psql('postgres',
+$node_p->wait_for_replay_catchup($node_s1);
+$node_s1->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
+my $result = $node_s1->safe_psql('postgres',
 	"SELECT slot_name FROM pg_replication_slots WHERE slot_name = '$fslotname' AND synced AND NOT temporary"
 );
 is($result, 'failover_slot', 'failover slot is synced');
 
-# Insert another row on node P and wait node S to catch up. We
+# Insert another row on node P and wait node S1 to catch up. We
 # intentionally performed this insert after syncing logical slot
 # as otherwise the local slot's (created during synchronization of
 # slot) xmin on standby could be ahead of the remote slot leading
 # to failure in synchronization.
 $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('second row')");
-$node_p->wait_for_replay_catchup($node_s);
+$node_p->wait_for_replay_catchup($node_s1);
 
 # Create subscription to test its removal
 my $dummy_sub = 'regress_sub_dummy';
 $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->stop;
+$node_p->wait_for_replay_catchup($node_s1);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--drop-all-publications'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s1);
+
+ok( $node_s1->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --drop-all-publications is run');
 
-# dry run mode on node S
+$node_s1->stop;
+
+# dry run mode on node S1
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--subscription' => 'sub1',
@@ -349,13 +364,14 @@ command_ok(
 		'--database' => $db1,
 		'--database' => $db2,
 	],
-	'run pg_createsubscriber --dry-run on node S');
+	'run pg_createsubscriber --dry-run on node S1');
 
-# Check if node S is still a standby
-$node_s->start;
-is($node_s->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
-	't', 'standby is in recovery');
-$node_s->stop;
+# Check if node S1 is still a standby
+$node_s1->start;
+is( $node_s1->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
+	't',
+	'standby is in recovery');
+$node_s1->stop;
 
 # pg_createsubscriber can run without --databases option
 command_ok(
@@ -363,35 +379,37 @@ command_ok(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--replication-slot' => 'replslot1',
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
+# Run pg_createsubscriber on node S1.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase and
+# --drop-all-publications option
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose', '--verbose',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--replication-slot' => 'replslot1',
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--drop-all-publications',
 	],
-	'run pg_createsubscriber on node S');
+	'run pg_createsubscriber on node S1');
 
 # Confirm the physical replication slot has been removed
 $result = $node_p->safe_psql($db1,
@@ -406,11 +424,15 @@ $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('third row')");
 $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 
 # Start subscriber
-$node_s->start;
+$node_s1->start;
+
+# Confirm publications are removed from the subscriber node
+is($node_s1->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications dropped after --drop-all-publications is run');
 
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
-is( $node_s->safe_psql(
+is( $node_s1->safe_psql(
 		'postgres',
 		"SELECT count(1) = 0 FROM pg_subscription WHERE subtwophasestate = 'd'"
 	),
@@ -418,50 +440,103 @@ is( $node_s->safe_psql(
 	'subscriptions are created with the two-phase option enabled');
 
 # Confirm the pre-existing subscription has been removed
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT count(*) FROM pg_subscription WHERE subname = '$dummy_sub'
 ));
 is($result, qq(0), 'pre-existing subscription was dropped');
 
 # Get subscription names
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT subname FROM pg_subscription WHERE subname ~ '^pg_createsubscriber_'
 ));
 my @subnames = split("\n", $result);
 
 # Wait subscriber to catch up
-$node_s->wait_for_subscription_sync($node_p, $subnames[0]);
-$node_s->wait_for_subscription_sync($node_p, $subnames[1]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[0]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[1]);
 
 # Confirm the failover slot has been removed
-$result = $node_s->safe_psql($db1,
+$result = $node_s1->safe_psql($db1,
 	"SELECT count(*) FROM pg_replication_slots WHERE slot_name = '$fslotname'"
 );
 is($result, qq(0), 'failover slot was removed');
 
 # Check result in database $db1
-$result = $node_s->safe_psql($db1, 'SELECT * FROM tbl1');
+$result = $node_s1->safe_psql($db1, 'SELECT * FROM tbl1');
 is( $result, qq(first row
 second row
 third row),
 	"logical replication works in database $db1");
 
 # Check result in database $db2
-$result = $node_s->safe_psql($db2, 'SELECT * FROM tbl2');
+$result = $node_s1->safe_psql($db2, 'SELECT * FROM tbl2');
 is($result, qq(row 1), "logical replication works in database $db2");
 
 # Different system identifier?
 my $sysid_p = $node_p->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
-my $sysid_s = $node_s->safe_psql('postgres',
+my $sysid_s = $node_s1->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Reuse node P as primary
+# Set up node S2 as standby linking to node P
+$node_p->backup('backup_3');
+my $node_s2 = PostgreSQL::Test::Cluster->new('node_s2');
+$node_s2->init_from_backup($node_p, 'backup_3', has_streaming => 1);
+$node_s2->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$pconnstr'
+       max_logical_replication_workers = 5
+       ]);
+$node_s2->set_standby_mode();
+$node_s2->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_p, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_p->safe_psql(
+	$db3, qq(
+	CREATE PUBLICATION test_pub3 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub4 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s2);
+
+# Verify the existing publications
+ok( $node_s2->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_s2->stop;
+
+# Run pg_createsubscriber on node S2 without '--drop-all-publications'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_s2->data_dir,
+		'--publisher-server' => $node_p->connstr($db3),
+		'--socketdir' => $node_s2->host,
+		'--subscriber-port' => $node_s2->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --drop-all-publications on node S2');
+
+$node_s2->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_s2->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
 # clean up
 $node_p->teardown_node;
-$node_s->teardown_node;
+$node_s1->teardown_node;
+$node_s2->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
 
-- 
2.34.1

From d8b08fad7e3ef0062e95a7c6e977653dc40ff67e Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Fri, 28 Feb 2025 14:44:23 +0530
Subject: [PATCH v15] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--drop-all-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The '--drop-all-publications' option allows users to remove replicated
publications from the subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed. By default, publications are preserved to avoid unintended
data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 +
 src/bin/pg_basebackup/pg_createsubscriber.c   |  94 ++++++--
 .../t/040_pg_createsubscriber.pl              | 201 ++++++++++++------
 3 files changed, 221 insertions(+), 85 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..80eb0e79629 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--drop-all-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index a5a2d61165d..027f195b45b 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -44,6 +44,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		drop_publications;	/* drop all publications */
 };
 
 /* per-database publication/subscription info */
@@ -91,7 +92,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool drop_all_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -109,7 +111,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication_by_name(PGconn *conn, const char *pubname,
+									 struct LogicalRepInfo *dbinfo);
+static void check_and_drop_existing_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -192,7 +196,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfos.dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfos.dbinfo[i]);
+					drop_publication_by_name(conn, dbinfos.dbinfo[i].pubname,
+											 &dbinfos.dbinfo[i]);
 				if (dbinfos.dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfos.dbinfo[i], dbinfos.dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -234,6 +239,9 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --drop-all-publications\n"
+			 "                                  drop all publications from specified databases\n"
+			 "                                  on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1171,10 +1179,13 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' parameter is true, existing
+ * publications on the subscriber will be dropped before creating new
+ * subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool drop_all_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1192,11 +1203,16 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publication was created before the consistent LSN, it
+		 * remains on the subscriber even after the physical replica is
+		 * promoted. Remove this publication from the subscriber because it
+		 * has no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (drop_all_publications)
+			check_and_drop_existing_publications(conn, &dbinfo[i]);
+		else
+			drop_publication_by_name(conn, dbinfo[i].pubname, &dbinfo[i]);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1661,26 +1677,22 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication of the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication_by_name(PGconn *conn, const char *pubname,
+						 struct LogicalRepInfo *dbinfo)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
 
-	Assert(conn != NULL);
-
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	char	   *pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbinfo->dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
-	PQfreemem(pubname_esc);
-
 	pg_log_debug("command is: %s", str->data);
 
 	if (!dry_run)
@@ -1689,8 +1701,11 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbinfo->dbname,
+						 PQresultErrorMessage(res));
+
+			if (strcmp(pubname, dbinfos.dbinfo->pubname) == 0)
+				dbinfo->made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1703,9 +1718,39 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		PQclear(res);
 	}
 
+	PQfreemem(pubname_esc);
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Check and drop existing publications on the subscriber.
+ */
+static void
+check_and_drop_existing_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbinfo->dbname);
+
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
+
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication_by_name(conn, PQgetvalue(res, i, 0), dbinfo);
+
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbinfo->dbname);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1907,6 +1952,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"drop-all-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1976,6 +2022,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.drop_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1993,11 +2040,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.drop_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2278,7 +2328,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfos.dbinfo, consistent_lsn);
+	setup_subscriber(dbinfos.dbinfo, consistent_lsn, opt.drop_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfos.dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..22db6a44971 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -150,18 +150,18 @@ my $slotname = 'physical_slot';
 $node_p->safe_psql($db2,
 	"SELECT pg_create_physical_replication_slot('$slotname')");
 
-# Set up node S as standby linking to node P
+# Set up node S1 as standby linking to node P
 $node_p->backup('backup_1');
-my $node_s = PostgreSQL::Test::Cluster->new('node_s');
-$node_s->init_from_backup($node_p, 'backup_1', has_streaming => 1);
-$node_s->append_conf(
+my $node_s1 = PostgreSQL::Test::Cluster->new('node_s1');
+$node_s1->init_from_backup($node_p, 'backup_1', has_streaming => 1);
+$node_s1->append_conf(
 	'postgresql.conf', qq[
 primary_slot_name = '$slotname'
 primary_conninfo = '$pconnstr dbname=postgres'
 hot_standby_feedback = on
 ]);
-$node_s->set_standby_mode();
-$node_s->start;
+$node_s1->set_standby_mode();
+$node_s1->start;
 
 # Set up node T as standby linking to node P then promote it
 my $node_t = PostgreSQL::Test::Cluster->new('node_t');
@@ -192,10 +192,10 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
@@ -215,10 +215,10 @@ command_fails(
 	],
 	'subscriber data directory is not a copy of the source database cluster');
 
-# Set up node C as standby linking to node S
-$node_s->backup('backup_2');
+# Set up node C as standby linking to node S1
+$node_s1->backup('backup_2');
 my $node_c = PostgreSQL::Test::Cluster->new('node_c');
-$node_c->init_from_backup($node_s, 'backup_2', has_streaming => 1);
+$node_c->init_from_backup($node_s1, 'backup_2', has_streaming => 1);
 $node_c->adjust_conf('postgresql.conf', 'primary_slot_name', undef);
 $node_c->set_standby_mode();
 
@@ -229,7 +229,7 @@ command_fails(
 		'--verbose',
 		'--dry-run',
 		'--pgdata' => $node_c->data_dir,
-		'--publisher-server' => $node_s->connstr($db1),
+		'--publisher-server' => $node_s1->connstr($db1),
 		'--socketdir' => $node_c->host,
 		'--subscriber-port' => $node_c->port,
 		'--database' => $db1,
@@ -246,16 +246,16 @@ max_wal_senders = 1
 max_worker_processes = 2
 });
 $node_p->restart;
-$node_s->stop;
+$node_s1->stop;
 command_fails(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 
@@ -271,8 +271,8 @@ max_wal_senders = 10
 max_worker_processes = 8
 });
 
-# Check some unmet conditions on node S
-$node_s->append_conf(
+# Check some unmet conditions on node S1
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 1
 max_logical_replication_workers = 1
@@ -283,15 +283,15 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
-	'standby contains unmet conditions on node S');
-$node_s->append_conf(
+	'standby contains unmet conditions on node S1');
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 10
 max_logical_replication_workers = 4
@@ -305,43 +305,58 @@ my $fslotname = 'failover_slot';
 $node_p->safe_psql($db1,
 	"SELECT pg_create_logical_replication_slot('$fslotname', 'pgoutput', false, false, true)"
 );
-$node_s->start;
+$node_s1->start;
 # Wait for the standby to catch up so that the standby is not lagging behind
 # the failover slot.
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
-my $result = $node_s->safe_psql('postgres',
+$node_p->wait_for_replay_catchup($node_s1);
+$node_s1->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
+my $result = $node_s1->safe_psql('postgres',
 	"SELECT slot_name FROM pg_replication_slots WHERE slot_name = '$fslotname' AND synced AND NOT temporary"
 );
 is($result, 'failover_slot', 'failover slot is synced');
 
-# Insert another row on node P and wait node S to catch up. We
+# Insert another row on node P and wait node S1 to catch up. We
 # intentionally performed this insert after syncing logical slot
 # as otherwise the local slot's (created during synchronization of
 # slot) xmin on standby could be ahead of the remote slot leading
 # to failure in synchronization.
 $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('second row')");
-$node_p->wait_for_replay_catchup($node_s);
+$node_p->wait_for_replay_catchup($node_s1);
 
 # Create subscription to test its removal
 my $dummy_sub = 'regress_sub_dummy';
 $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->stop;
+$node_p->wait_for_replay_catchup($node_s1);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--drop-all-publications'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s1);
+
+ok( $node_s1->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --drop-all-publications is run');
 
-# dry run mode on node S
+$node_s1->stop;
+
+# dry run mode on node S1
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--subscription' => 'sub1',
@@ -349,13 +364,14 @@ command_ok(
 		'--database' => $db1,
 		'--database' => $db2,
 	],
-	'run pg_createsubscriber --dry-run on node S');
+	'run pg_createsubscriber --dry-run on node S1');
 
-# Check if node S is still a standby
-$node_s->start;
-is($node_s->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
-	't', 'standby is in recovery');
-$node_s->stop;
+# Check if node S1 is still a standby
+$node_s1->start;
+is( $node_s1->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
+	't',
+	'standby is in recovery');
+$node_s1->stop;
 
 # pg_createsubscriber can run without --databases option
 command_ok(
@@ -363,35 +379,37 @@ command_ok(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--replication-slot' => 'replslot1',
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
+# Run pg_createsubscriber on node S1.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase and
+# --drop-all-publications option
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose', '--verbose',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--replication-slot' => 'replslot1',
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--drop-all-publications',
 	],
-	'run pg_createsubscriber on node S');
+	'run pg_createsubscriber on node S1');
 
 # Confirm the physical replication slot has been removed
 $result = $node_p->safe_psql($db1,
@@ -406,11 +424,15 @@ $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('third row')");
 $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 
 # Start subscriber
-$node_s->start;
+$node_s1->start;
+
+# Confirm publications are removed from the subscriber node
+is($node_s1->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications dropped after --drop-all-publications is run');
 
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
-is( $node_s->safe_psql(
+is( $node_s1->safe_psql(
 		'postgres',
 		"SELECT count(1) = 0 FROM pg_subscription WHERE subtwophasestate = 'd'"
 	),
@@ -418,50 +440,103 @@ is( $node_s->safe_psql(
 	'subscriptions are created with the two-phase option enabled');
 
 # Confirm the pre-existing subscription has been removed
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT count(*) FROM pg_subscription WHERE subname = '$dummy_sub'
 ));
 is($result, qq(0), 'pre-existing subscription was dropped');
 
 # Get subscription names
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT subname FROM pg_subscription WHERE subname ~ '^pg_createsubscriber_'
 ));
 my @subnames = split("\n", $result);
 
 # Wait subscriber to catch up
-$node_s->wait_for_subscription_sync($node_p, $subnames[0]);
-$node_s->wait_for_subscription_sync($node_p, $subnames[1]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[0]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[1]);
 
 # Confirm the failover slot has been removed
-$result = $node_s->safe_psql($db1,
+$result = $node_s1->safe_psql($db1,
 	"SELECT count(*) FROM pg_replication_slots WHERE slot_name = '$fslotname'"
 );
 is($result, qq(0), 'failover slot was removed');
 
 # Check result in database $db1
-$result = $node_s->safe_psql($db1, 'SELECT * FROM tbl1');
+$result = $node_s1->safe_psql($db1, 'SELECT * FROM tbl1');
 is( $result, qq(first row
 second row
 third row),
 	"logical replication works in database $db1");
 
 # Check result in database $db2
-$result = $node_s->safe_psql($db2, 'SELECT * FROM tbl2');
+$result = $node_s1->safe_psql($db2, 'SELECT * FROM tbl2');
 is($result, qq(row 1), "logical replication works in database $db2");
 
 # Different system identifier?
 my $sysid_p = $node_p->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
-my $sysid_s = $node_s->safe_psql('postgres',
+my $sysid_s = $node_s1->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Reuse node P as primary
+# Set up node S2 as standby linking to node P
+$node_p->backup('backup_3');
+my $node_s2 = PostgreSQL::Test::Cluster->new('node_s2');
+$node_s2->init_from_backup($node_p, 'backup_3', has_streaming => 1);
+$node_s2->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$pconnstr'
+       max_logical_replication_workers = 5
+       ]);
+$node_s2->set_standby_mode();
+$node_s2->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_p, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_p->safe_psql(
+	$db3, qq(
+	CREATE PUBLICATION test_pub3 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub4 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s2);
+
+# Verify the existing publications
+ok( $node_s2->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_s2->stop;
+
+# Run pg_createsubscriber on node S2 without '--drop-all-publications'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_s2->data_dir,
+		'--publisher-server' => $node_p->connstr($db3),
+		'--socketdir' => $node_s2->host,
+		'--subscriber-port' => $node_s2->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --drop-all-publications on node S2');
+
+$node_s2->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_s2->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
 # clean up
 $node_p->teardown_node;
-$node_s->teardown_node;
+$node_s1->teardown_node;
+$node_s2->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
 
-- 
2.41.0.windows.3

From d89d693f59301f055ee29efb2bd5baa01a0f6d48 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Fri, 28 Feb 2025 14:44:23 +0530
Subject: [PATCH v16] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--drop-all-publications' option in the
'pg_createsubscriber' utility.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The '--drop-all-publications' option allows users to remove replicated
publications from the subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed. By default, publications are preserved to avoid unintended
data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  11 +
 src/bin/pg_basebackup/pg_createsubscriber.c   |  94 ++++++--
 .../t/040_pg_createsubscriber.pl              | 201 ++++++++++++------
 3 files changed, 221 insertions(+), 85 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..80eb0e79629 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -87,6 +87,17 @@ PostgreSQL documentation
    command-line arguments:
 
    <variablelist>
+    <varlistentry>
+     <term><option>-c</option></term>
+     <term><option>--drop-all-publications</option></term>
+     <listitem>
+      <para>
+       Remove all existing publications from specified databases on the target
+       server.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-d <replaceable class="parameter">dbname</replaceable></option></term>
      <term><option>--database=<replaceable class="parameter">dbname</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index a5a2d61165d..1f7a608e45a 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -44,6 +44,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	bool		drop_publications;	/* drop all publications */
 };
 
 /* per-database publication/subscription info */
@@ -91,7 +92,8 @@ static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
 static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+							 const char *consistent_lsn,
+							 bool drop_all_publications);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -109,7 +111,10 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication_by_name(PGconn *conn, const char *pubname,
+									 struct LogicalRepInfo *dbinfo);
+static void check_and_drop_existing_publications(PGconn *conn,
+												 struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -192,7 +197,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfos.dbinfo[i].made_publication)
-					drop_publication(conn, &dbinfos.dbinfo[i]);
+					drop_publication_by_name(conn, dbinfos.dbinfo[i].pubname,
+											 &dbinfos.dbinfo[i]);
 				if (dbinfos.dbinfo[i].made_replslot)
 					drop_replication_slot(conn, &dbinfos.dbinfo[i], dbinfos.dbinfo[i].replslotname);
 				disconnect_database(conn, false);
@@ -234,6 +240,9 @@ usage(void)
 	printf(_("Usage:\n"));
 	printf(_("  %s [OPTION]...\n"), progname);
 	printf(_("\nOptions:\n"));
+	printf(_("  -c  --drop-all-publications\n"
+			 "                                  drop all publications from specified databases\n"
+			 "                                  on the subscriber\n"));
 	printf(_("  -d, --database=DBNAME           database in which to create a subscription\n"));
 	printf(_("  -D, --pgdata=DATADIR            location for the subscriber data directory\n"));
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
@@ -1171,10 +1180,13 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'drop_publications' parameter is true, existing
+ * publications on the subscriber will be dropped before creating new
+ * subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn,
+				 bool drop_all_publications)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
@@ -1192,11 +1204,16 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publication was created before the consistent LSN, it
+		 * remains on the subscriber even after the physical replica is
+		 * promoted. Remove this publication from the subscriber because it
+		 * has no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (drop_all_publications)
+			check_and_drop_existing_publications(conn, &dbinfo[i]);
+		else
+			drop_publication_by_name(conn, dbinfo[i].pubname, &dbinfo[i]);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1661,26 +1678,22 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication of the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication_by_name(PGconn *conn, const char *pubname,
+						 struct LogicalRepInfo *dbinfo)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
-	char	   *pubname_esc;
-
-	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	char	   *pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbinfo->dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
-	PQfreemem(pubname_esc);
-
 	pg_log_debug("command is: %s", str->data);
 
 	if (!dry_run)
@@ -1689,8 +1702,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbinfo->dbname, PQresultErrorMessage(res));
+
+			if (strcmp(pubname, dbinfo->pubname) == 0)
+				dbinfo->made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1703,9 +1718,39 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		PQclear(res);
 	}
 
+	PQfreemem(pubname_esc);
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Check and drop existing publications on the subscriber.
+ */
+static void
+check_and_drop_existing_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbinfo->dbname);
+
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
+
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication_by_name(conn, PQgetvalue(res, i, 0), dbinfo);
+
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbinfo->dbname);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1907,6 +1952,7 @@ main(int argc, char **argv)
 {
 	static struct option long_options[] =
 	{
+		{"drop-all-publications", no_argument, NULL, 'c'},
 		{"database", required_argument, NULL, 'd'},
 		{"pgdata", required_argument, NULL, 'D'},
 		{"dry-run", no_argument, NULL, 'n'},
@@ -1976,6 +2022,7 @@ main(int argc, char **argv)
 		0
 	};
 	opt.recovery_timeout = 0;
+	opt.drop_publications = false;
 
 	/*
 	 * Don't allow it to be run as root. It uses pg_ctl which does not allow
@@ -1993,11 +2040,14 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "cd:D:np:P:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
 		{
+			case 'c':
+				opt.drop_publications = true;
+				break;
 			case 'd':
 				if (!simple_string_list_member(&opt.database_names, optarg))
 				{
@@ -2278,7 +2328,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfos.dbinfo, consistent_lsn);
+	setup_subscriber(dbinfos.dbinfo, consistent_lsn, opt.drop_publications);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfos.dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..22db6a44971 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -150,18 +150,18 @@ my $slotname = 'physical_slot';
 $node_p->safe_psql($db2,
 	"SELECT pg_create_physical_replication_slot('$slotname')");
 
-# Set up node S as standby linking to node P
+# Set up node S1 as standby linking to node P
 $node_p->backup('backup_1');
-my $node_s = PostgreSQL::Test::Cluster->new('node_s');
-$node_s->init_from_backup($node_p, 'backup_1', has_streaming => 1);
-$node_s->append_conf(
+my $node_s1 = PostgreSQL::Test::Cluster->new('node_s1');
+$node_s1->init_from_backup($node_p, 'backup_1', has_streaming => 1);
+$node_s1->append_conf(
 	'postgresql.conf', qq[
 primary_slot_name = '$slotname'
 primary_conninfo = '$pconnstr dbname=postgres'
 hot_standby_feedback = on
 ]);
-$node_s->set_standby_mode();
-$node_s->start;
+$node_s1->set_standby_mode();
+$node_s1->start;
 
 # Set up node T as standby linking to node P then promote it
 my $node_t = PostgreSQL::Test::Cluster->new('node_t');
@@ -192,10 +192,10 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
@@ -215,10 +215,10 @@ command_fails(
 	],
 	'subscriber data directory is not a copy of the source database cluster');
 
-# Set up node C as standby linking to node S
-$node_s->backup('backup_2');
+# Set up node C as standby linking to node S1
+$node_s1->backup('backup_2');
 my $node_c = PostgreSQL::Test::Cluster->new('node_c');
-$node_c->init_from_backup($node_s, 'backup_2', has_streaming => 1);
+$node_c->init_from_backup($node_s1, 'backup_2', has_streaming => 1);
 $node_c->adjust_conf('postgresql.conf', 'primary_slot_name', undef);
 $node_c->set_standby_mode();
 
@@ -229,7 +229,7 @@ command_fails(
 		'--verbose',
 		'--dry-run',
 		'--pgdata' => $node_c->data_dir,
-		'--publisher-server' => $node_s->connstr($db1),
+		'--publisher-server' => $node_s1->connstr($db1),
 		'--socketdir' => $node_c->host,
 		'--subscriber-port' => $node_c->port,
 		'--database' => $db1,
@@ -246,16 +246,16 @@ max_wal_senders = 1
 max_worker_processes = 2
 });
 $node_p->restart;
-$node_s->stop;
+$node_s1->stop;
 command_fails(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 
@@ -271,8 +271,8 @@ max_wal_senders = 10
 max_worker_processes = 8
 });
 
-# Check some unmet conditions on node S
-$node_s->append_conf(
+# Check some unmet conditions on node S1
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 1
 max_logical_replication_workers = 1
@@ -283,15 +283,15 @@ command_fails(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--database' => $db1,
 		'--database' => $db2,
 	],
-	'standby contains unmet conditions on node S');
-$node_s->append_conf(
+	'standby contains unmet conditions on node S1');
+$node_s1->append_conf(
 	'postgresql.conf', q{
 max_replication_slots = 10
 max_logical_replication_workers = 4
@@ -305,43 +305,58 @@ my $fslotname = 'failover_slot';
 $node_p->safe_psql($db1,
 	"SELECT pg_create_logical_replication_slot('$fslotname', 'pgoutput', false, false, true)"
 );
-$node_s->start;
+$node_s1->start;
 # Wait for the standby to catch up so that the standby is not lagging behind
 # the failover slot.
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
-my $result = $node_s->safe_psql('postgres',
+$node_p->wait_for_replay_catchup($node_s1);
+$node_s1->safe_psql('postgres', "SELECT pg_sync_replication_slots()");
+my $result = $node_s1->safe_psql('postgres',
 	"SELECT slot_name FROM pg_replication_slots WHERE slot_name = '$fslotname' AND synced AND NOT temporary"
 );
 is($result, 'failover_slot', 'failover slot is synced');
 
-# Insert another row on node P and wait node S to catch up. We
+# Insert another row on node P and wait node S1 to catch up. We
 # intentionally performed this insert after syncing logical slot
 # as otherwise the local slot's (created during synchronization of
 # slot) xmin on standby could be ahead of the remote slot leading
 # to failure in synchronization.
 $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('second row')");
-$node_p->wait_for_replay_catchup($node_s);
+$node_p->wait_for_replay_catchup($node_s1);
 
 # Create subscription to test its removal
 my $dummy_sub = 'regress_sub_dummy';
 $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
-$node_p->wait_for_replay_catchup($node_s);
-$node_s->stop;
+$node_p->wait_for_replay_catchup($node_s1);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--drop-all-publications'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s1);
+
+ok( $node_s1->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --drop-all-publications is run');
 
-# dry run mode on node S
+$node_s1->stop;
+
+# dry run mode on node S1
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--subscription' => 'sub1',
@@ -349,13 +364,14 @@ command_ok(
 		'--database' => $db1,
 		'--database' => $db2,
 	],
-	'run pg_createsubscriber --dry-run on node S');
+	'run pg_createsubscriber --dry-run on node S1');
 
-# Check if node S is still a standby
-$node_s->start;
-is($node_s->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
-	't', 'standby is in recovery');
-$node_s->stop;
+# Check if node S1 is still a standby
+$node_s1->start;
+is( $node_s1->safe_psql('postgres', 'SELECT pg_catalog.pg_is_in_recovery()'),
+	't',
+	'standby is in recovery');
+$node_s1->stop;
 
 # pg_createsubscriber can run without --databases option
 command_ok(
@@ -363,35 +379,37 @@ command_ok(
 		'pg_createsubscriber',
 		'--verbose',
 		'--dry-run',
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--replication-slot' => 'replslot1',
 	],
 	'run pg_createsubscriber without --databases');
 
-# Run pg_createsubscriber on node S.  --verbose is used twice
+# Run pg_createsubscriber on node S1.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase and
+# --drop-all-publications option
 command_ok(
 	[
 		'pg_createsubscriber',
 		'--verbose', '--verbose',
 		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
-		'--pgdata' => $node_s->data_dir,
+		'--pgdata' => $node_s1->data_dir,
 		'--publisher-server' => $node_p->connstr($db1),
-		'--socketdir' => $node_s->host,
-		'--subscriber-port' => $node_s->port,
+		'--socketdir' => $node_s1->host,
+		'--subscriber-port' => $node_s1->port,
 		'--publication' => 'pub1',
 		'--publication' => 'pub2',
 		'--replication-slot' => 'replslot1',
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--drop-all-publications',
 	],
-	'run pg_createsubscriber on node S');
+	'run pg_createsubscriber on node S1');
 
 # Confirm the physical replication slot has been removed
 $result = $node_p->safe_psql($db1,
@@ -406,11 +424,15 @@ $node_p->safe_psql($db1, "INSERT INTO tbl1 VALUES('third row')");
 $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 
 # Start subscriber
-$node_s->start;
+$node_s1->start;
+
+# Confirm publications are removed from the subscriber node
+is($node_s1->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications dropped after --drop-all-publications is run');
 
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
-is( $node_s->safe_psql(
+is( $node_s1->safe_psql(
 		'postgres',
 		"SELECT count(1) = 0 FROM pg_subscription WHERE subtwophasestate = 'd'"
 	),
@@ -418,50 +440,103 @@ is( $node_s->safe_psql(
 	'subscriptions are created with the two-phase option enabled');
 
 # Confirm the pre-existing subscription has been removed
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT count(*) FROM pg_subscription WHERE subname = '$dummy_sub'
 ));
 is($result, qq(0), 'pre-existing subscription was dropped');
 
 # Get subscription names
-$result = $node_s->safe_psql(
+$result = $node_s1->safe_psql(
 	'postgres', qq(
 	SELECT subname FROM pg_subscription WHERE subname ~ '^pg_createsubscriber_'
 ));
 my @subnames = split("\n", $result);
 
 # Wait subscriber to catch up
-$node_s->wait_for_subscription_sync($node_p, $subnames[0]);
-$node_s->wait_for_subscription_sync($node_p, $subnames[1]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[0]);
+$node_s1->wait_for_subscription_sync($node_p, $subnames[1]);
 
 # Confirm the failover slot has been removed
-$result = $node_s->safe_psql($db1,
+$result = $node_s1->safe_psql($db1,
 	"SELECT count(*) FROM pg_replication_slots WHERE slot_name = '$fslotname'"
 );
 is($result, qq(0), 'failover slot was removed');
 
 # Check result in database $db1
-$result = $node_s->safe_psql($db1, 'SELECT * FROM tbl1');
+$result = $node_s1->safe_psql($db1, 'SELECT * FROM tbl1');
 is( $result, qq(first row
 second row
 third row),
 	"logical replication works in database $db1");
 
 # Check result in database $db2
-$result = $node_s->safe_psql($db2, 'SELECT * FROM tbl2');
+$result = $node_s1->safe_psql($db2, 'SELECT * FROM tbl2');
 is($result, qq(row 1), "logical replication works in database $db2");
 
 # Different system identifier?
 my $sysid_p = $node_p->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
-my $sysid_s = $node_s->safe_psql('postgres',
+my $sysid_s = $node_s1->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Reuse node P as primary
+# Set up node S2 as standby linking to node P
+$node_p->backup('backup_3');
+my $node_s2 = PostgreSQL::Test::Cluster->new('node_s2');
+$node_s2->init_from_backup($node_p, 'backup_3', has_streaming => 1);
+$node_s2->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$pconnstr'
+       max_logical_replication_workers = 5
+       ]);
+$node_s2->set_standby_mode();
+$node_s2->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_p, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_p->safe_psql(
+	$db3, qq(
+	CREATE PUBLICATION test_pub3 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub4 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s2);
+
+# Verify the existing publications
+ok( $node_s2->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_s2->stop;
+
+# Run pg_createsubscriber on node S2 without '--drop-all-publications'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_s2->data_dir,
+		'--publisher-server' => $node_p->connstr($db3),
+		'--socketdir' => $node_s2->host,
+		'--subscriber-port' => $node_s2->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --drop-all-publications on node S2');
+
+$node_s2->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_s2->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
 # clean up
 $node_p->teardown_node;
-$node_s->teardown_node;
+$node_s1->teardown_node;
+$node_s2->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
 
-- 
2.41.0.windows.3

From f2d5fde18e891f003f913a27a546cc61f2d66440 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v17] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the objects to be removed from the subscriber. This patch
adds supports to specify 'publications' as objects to remove.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during streaming replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command.

The '--remove' option allows users to remove replicated publications from the
subscriber when setting up logical replication.
This is particularly useful when publications created in a previous setup are
no longer needed. By default, publications are preserved to avoid unintended
data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  19 +++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 119 ++++++++++++++----
 .../t/040_pg_createsubscriber.pl              |  78 +++++++++++-
 3 files changed, 192 insertions(+), 24 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..09847f1d83c 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,25 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-r</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all given objects from specified databases on the target
+       server. Multiple objects can be selected by writing multiple
+       <option>-r</option> switches. As of now, the only supported object is
+       <literal>publications</literal>. This option is useful when
+       transitioning from streaming replication to logical replication as
+       existing objects may no longer be needed. Before using this option,
+       back up any manually created publications using
+       <application>pg_dump</application> to avoid data loss.
+       If multiple publications exist, they will be logged individually for
+       better traceability.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..5b1bb4a8115 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECT_PUBLICATIONS  0x1
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList remove_objects;	/* list of objects to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,7 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	uint32		remove_objects; /* flag to remove objects on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -90,8 +93,7 @@ static char *generate_object_name(PGconn *conn);
 static void check_publisher(const struct LogicalRepInfo *dbinfo);
 static char *setup_publisher(struct LogicalRepInfo *dbinfo);
 static void check_subscriber(const struct LogicalRepInfo *dbinfo);
-static void setup_subscriber(struct LogicalRepInfo *dbinfo,
-							 const char *consistent_lsn);
+static void setup_subscriber(const char *consistent_lsn);
 static void setup_recovery(const struct LogicalRepInfo *dbinfo, const char *datadir,
 						   const char *lsn);
 static void drop_primary_replication_slot(struct LogicalRepInfo *dbinfo,
@@ -109,7 +111,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+							 const char *pubname);
+static void drop_all_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +198,7 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo, dbinfo->pubname);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +245,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -r, --remove=OBJECT             all objects to be removed from specified databases\n"
+			 "                                  on the subscriber\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1173,17 +1179,19 @@ check_and_drop_existing_subscriptions(PGconn *conn,
 /*
  * Create the subscriptions, adjust the initial location for logical
  * replication and enable the subscriptions. That's the last step for logical
- * replication setup.
+ * replication setup. If 'remove' parameter is specified, existing publications
+ * on the subscriber will be dropped before creating new subscriptions.
  */
 static void
-setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
+setup_subscriber(const char *consistent_lsn)
 {
 	for (int i = 0; i < num_dbs; i++)
 	{
 		PGconn	   *conn;
+		struct LogicalRepInfo *dbinfo = &dbinfos.dbinfo[i];
 
 		/* Connect to subscriber. */
-		conn = connect_database(dbinfo[i].subconninfo, true);
+		conn = connect_database(dbinfo->subconninfo, true);
 
 		/*
 		 * We don't need the pre-existing subscriptions on the newly formed
@@ -1191,22 +1199,27 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * get some unwarranted data or can lead to ERRORs in connecting to
 		 * such nodes.
 		 */
-		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
+		check_and_drop_existing_subscriptions(conn, dbinfo);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publications were created before the consistent LSN, they
+		 * remain on the subscriber even after the physical replica is
+		 * promoted. Remove these publications from the subscriber because
+		 * they have no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (dbinfos.remove_objects & OBJECT_PUBLICATIONS)
+			drop_all_publications(conn, dbinfo);
+		else
+			drop_publication(conn, dbinfo, dbinfo->pubname);
 
-		create_subscription(conn, &dbinfo[i]);
+		create_subscription(conn, dbinfo);
 
 		/* Set the replication progress to the correct LSN */
-		set_replication_progress(conn, &dbinfo[i], consistent_lsn);
+		set_replication_progress(conn, dbinfo, consistent_lsn);
 
 		/* Enable subscription */
-		enable_subscription(conn, &dbinfo[i]);
+		enable_subscription(conn, dbinfo);
 
 		disconnect_database(conn, false);
 	}
@@ -1663,10 +1676,10 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication of the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo, const char *pubname)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1687,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbinfo->dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,7 +1704,7 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
+						 pubname, dbinfo->dbname, PQresultErrorMessage(res));
 			dbinfo->made_publication = false;	/* don't try again. */
 
 			/*
@@ -1708,6 +1721,35 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Drop all publications on the database.
+ */
+static void
+drop_all_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbinfo->dbname);
+
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		return;
+	}
+
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication(conn, dbinfo, PQgetvalue(res, i, 0));
+
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbinfo->dbname);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1956,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'r'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2038,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:r:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2068,17 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'r':
+				if (!simple_string_list_member(&opt.remove_objects, optarg))
+				{
+					simple_string_list_append(&opt.remove_objects, optarg);
+				}
+				else
+				{
+					pg_log_error("object \"%s\" specified more than once", optarg);
+					exit(1);
+				}
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2243,27 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the objects specified for removal from the subscriber */
+	dbinfos.remove_objects = 0x0;
+	if (opt.remove_objects.head != NULL)
+	{
+		SimpleStringListCell *cell;
+
+		for (cell = opt.remove_objects.head; cell; cell = cell->next)
+		{
+			if (strcmp(cell->val, "publications") == 0)
+			{
+				dbinfos.remove_objects |= OBJECT_PUBLICATIONS;
+			}
+			else
+			{
+				pg_log_error("wrong remove object is specified");
+				pg_log_error_hint("Only \"publications\" can be removed.");
+				exit(1);
+			}
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
@@ -2280,7 +2355,7 @@ main(int argc, char **argv)
 	 * point to the LSN reported by setup_publisher().  It also cleans up
 	 * publications created by this tool and replication to the standby.
 	 */
-	setup_subscriber(dbinfos.dbinfo, consistent_lsn);
+	setup_subscriber(consistent_lsn);
 
 	/* Remove primary_slot_name if it exists on primary */
 	drop_primary_replication_slot(dbinfos.dbinfo, primary_slot_name);
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..e25507b86ae 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications created before --remove is run');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +388,8 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and
+# --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +405,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +425,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications dropped after --remove is run');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
@@ -459,9 +480,62 @@ my $sysid_s = $node_s->safe_psql('postgres',
 	'SELECT system_identifier FROM pg_control_system()');
 ok($sysid_p != $sysid_s, 'system identifier was changed');
 
+# Reuse node P as primary
+# Set up node U as standby linking to node P
+$node_p->backup('backup_3');
+my $node_u = PostgreSQL::Test::Cluster->new('node_u');
+$node_u->init_from_backup($node_p, 'backup_3', has_streaming => 1);
+$node_u->append_conf(
+	'postgresql.conf', qq[
+       primary_conninfo = '$pconnstr'
+       max_logical_replication_workers = 5
+       ]);
+$node_u->set_standby_mode();
+$node_u->start;
+
+# Ensure there is a user database on the publisher
+my $db3 = generate_db($node_p, 'regression', 91, 127, '');
+
+# Create user-defined publications
+$node_p->safe_psql(
+	$db3, qq(
+	CREATE PUBLICATION test_pub3 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub4 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_u);
+
+# Verify the existing publications
+ok( $node_u->safe_psql($db3, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two publications are created before running pg_createsubscriber');
+
+$node_u->stop;
+
+# Run pg_createsubscriber on node U without '--remove'.
+# --verbose is used twice to show more information.
+command_ok(
+	[
+		'pg_createsubscriber',
+		'--verbose', '--verbose',
+		'--recovery-timeout' => $PostgreSQL::Test::Utils::timeout_default,
+		'--pgdata' => $node_u->data_dir,
+		'--publisher-server' => $node_p->connstr($db3),
+		'--socketdir' => $node_u->host,
+		'--subscriber-port' => $node_u->port,
+		'--database' => $db3,
+	],
+	'run pg_createsubscriber without --remove on node U');
+
+$node_u->start;
+
+# Confirm publications still remain after running 'pg_createsubscriber'
+is($node_u->safe_psql($db3, "SELECT COUNT(*) FROM pg_publication;"),
+	'2', 'all publications remain after running pg_createsubscriber');
+
 # clean up
 $node_p->teardown_node;
 $node_s->teardown_node;
+$node_u->teardown_node;
 $node_t->teardown_node;
 $node_f->teardown_node;
 
-- 
2.34.1

From 6272466ff10069a2079e0d700e6a6e12b6bfb7d5 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v18] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the object types to be removed from the subscriber.
This patch adds supports to specify 'publications' as an object type.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during physical replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command. By default, publications are preserved to avoid
unintended data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  19 +++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 110 +++++++++++++++---
 .../t/040_pg_createsubscriber.pl              |  25 +++-
 3 files changed, 135 insertions(+), 19 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..9d7426fede0 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,25 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-r</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all objects of the specified type from specified databases on the
+       target server. Multiple object types can be specified by writing multiple
+       <option>--remove</option> switches. As of now, the only supported object
+       type is <literal>publications</literal>. This option is useful when
+       transitioning from physical replication to logical replication as
+       existing objects may no longer be needed. Before using this option,
+       back up any manually created publications using
+       <application>pg_dump</application> to avoid data loss.
+       If multiple publications exist, they will be logged individually for
+       better traceability.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..48111dbd0d9 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECT_PUBLICATIONS  0x1
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList remove_objects;	/* list of objects to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,7 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	bits32		remove_objects; /* flag to remove objects on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -109,7 +112,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+							 const char *pubname);
+static void drop_all_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +199,7 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo, dbinfo->pubname);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +246,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -r, --remove=OBJECT             all objects to be removed from specified databases\n"
+			 "                                  on the subscriber\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1183,7 +1190,7 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		PGconn	   *conn;
 
 		/* Connect to subscriber. */
-		conn = connect_database(dbinfo[i].subconninfo, true);
+		conn = connect_database(dbinfos.dbinfo[i].subconninfo, true);
 
 		/*
 		 * We don't need the pre-existing subscriptions on the newly formed
@@ -1191,22 +1198,27 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 * get some unwarranted data or can lead to ERRORs in connecting to
 		 * such nodes.
 		 */
-		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
+		check_and_drop_existing_subscriptions(conn, &dbinfos.dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publications were created before the consistent LSN, they
+		 * remain on the subscriber even after the physical replica is
+		 * promoted. Remove these publications from the subscriber because
+		 * they have no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (dbinfos.remove_objects & OBJECT_PUBLICATIONS)
+			drop_all_publications(conn, &dbinfos.dbinfo[i]);
+		else
+			drop_publication(conn, &dbinfos.dbinfo[i], dbinfos.dbinfo[i].pubname);
 
-		create_subscription(conn, &dbinfo[i]);
+		create_subscription(conn, &dbinfos.dbinfo[i]);
 
 		/* Set the replication progress to the correct LSN */
-		set_replication_progress(conn, &dbinfo[i], consistent_lsn);
+		set_replication_progress(conn, &dbinfos.dbinfo[i], consistent_lsn);
 
 		/* Enable subscription */
-		enable_subscription(conn, &dbinfo[i]);
+		enable_subscription(conn, &dbinfos.dbinfo[i]);
 
 		disconnect_database(conn, false);
 	}
@@ -1663,10 +1675,10 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication of the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo, const char *pubname)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1686,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbinfo->dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,7 +1703,7 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
+						 pubname, dbinfo->dbname, PQresultErrorMessage(res));
 			dbinfo->made_publication = false;	/* don't try again. */
 
 			/*
@@ -1708,6 +1720,38 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Drop all publications on the database.
+ */
+static void
+drop_all_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	Assert(conn != NULL);
+
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbinfo->dbname);
+
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		disconnect_database(conn, false);
+		return;
+	}
+
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication(conn, dbinfo, PQgetvalue(res, i, 0));
+
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbinfo->dbname);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1958,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'r'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2040,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:r:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2070,17 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'r':
+				if (!simple_string_list_member(&opt.remove_objects, optarg))
+				{
+					simple_string_list_append(&opt.remove_objects, optarg);
+				}
+				else
+				{
+					pg_log_error("object \"%s\" specified more than once", optarg);
+					exit(1);
+				}
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2245,26 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the objects specified for removal from the subscriber */
+	dbinfos.remove_objects = 0x0;
+	if (opt.remove_objects.head != NULL)
+	{
+		for (SimpleStringListCell *cell = opt.remove_objects.head; cell; cell = cell->next)
+		{
+			if (pg_strcasecmp(cell->val, "publications") == 0 ||
+				pg_strcasecmp(cell->val, "all") == 0)
+			{
+				dbinfos.remove_objects |= OBJECT_PUBLICATIONS;
+			}
+			else
+			{
+				pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+				pg_log_error_hint("The valid options are: \"all\", \"publications\"");
+				exit(1);
+			}
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..2c9bd5bdb9e 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two pre-existing publications on subscriber');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +388,8 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and
+# --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +405,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +425,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications on subscriber have been removed');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
-- 
2.34.1

From 4949d93e71d786bdb665307a787f2ba4e56cba6f Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v19] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the object types to be removed from the subscriber.
This patch adds supports to specify 'publications' as an object type.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during physical replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin. Users should back up any manually created publications before
running this command. By default, publications are preserved to avoid
unintended data loss.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     | 19 ++++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 99 ++++++++++++++++---
 .../t/040_pg_createsubscriber.pl              | 25 ++++-
 3 files changed, 129 insertions(+), 14 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..45f3c0900c1 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,25 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-r</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all objects of the specified type from specified databases on the
+       target server. Multiple object types can be specified by using multiple
+       <option>--remove</option> switches. Currently, the supported type is
+       <literal>publications</literal>. This option is useful when
+       transitioning from physical replication to logical replication as
+       existing objects may no longer be needed. Before using this option,
+       back up any manually created publications using
+       <application>pg_dump</application> to avoid data loss.
+       If multiple publications exist, they will be logged individually for
+       better traceability.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..31573cc7f9f 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECT_PUBLICATIONS  0x1
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList remove_objects;	/* list of object types to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,7 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	bits32		remove_objects; /* flag to remove objects on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -109,7 +112,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo,
+							 const char *pubname);
+static void drop_all_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +199,7 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo, dbinfo->pubname);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +246,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -r, --remove=OBJECTTYPE         remove all objects of the specified type from specified\n"
+			 "                                  databases on the subscriber\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1194,11 +1201,16 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publications were created before the consistent LSN, they
+		 * remain on the subscriber even after the physical replica is
+		 * promoted. Remove these publications from the subscriber because
+		 * they have no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		if (dbinfos.remove_objects & OBJECT_PUBLICATIONS)
+			drop_all_publications(conn, &dbinfo[i]);
+		else
+			drop_publication(conn, &dbinfo[i], dbinfo[i].pubname);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1663,10 +1675,10 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication of the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo, const char *pubname)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1686,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbinfo->dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,7 +1703,7 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
+						 pubname, dbinfo->dbname, PQresultErrorMessage(res));
 			dbinfo->made_publication = false;	/* don't try again. */
 
 			/*
@@ -1708,6 +1720,38 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Drop all publications on the database.
+ */
+static void
+drop_all_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	Assert(conn != NULL);
+
+	pg_log_info("dropping all existing publications in database \"%s\"",
+				dbinfo->dbname);
+
+	/* Fetch all publication names */
+	res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
+	{
+		pg_log_error("could not obtain publication information: %s",
+					 PQresultErrorMessage(res));
+		PQclear(res);
+		disconnect_database(conn, false);
+		return;
+	}
+
+	/* Drop each publication */
+	for (int i = 0; i < PQntuples(res); i++)
+		drop_publication(conn, dbinfo, PQgetvalue(res, i, 0));
+
+	PQclear(res);
+	pg_log_info("dropped all publications in database \"%s\"", dbinfo->dbname);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1958,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'r'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2040,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:r:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2070,17 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'r':
+				if (!simple_string_list_member(&opt.remove_objects, optarg))
+				{
+					simple_string_list_append(&opt.remove_objects, optarg);
+				}
+				else
+				{
+					pg_log_error("object type \"%s\" is specified more than once for --remove", optarg);
+					exit(1);
+				}
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2245,25 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the object types specified for removal from the subscriber */
+	dbinfos.remove_objects = 0x0;
+	if (opt.remove_objects.head != NULL)
+	{
+		for (SimpleStringListCell *cell = opt.remove_objects.head; cell; cell = cell->next)
+		{
+			if (pg_strcasecmp(cell->val, "publications") == 0)
+			{
+				dbinfos.remove_objects |= OBJECT_PUBLICATIONS;
+			}
+			else
+			{
+				pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+				pg_log_error_hint("The valid option is: \"publications\"");
+				exit(1);
+			}
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..2c9bd5bdb9e 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two pre-existing publications on subscriber');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +388,8 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and
+# --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +405,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +425,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications on subscriber have been removed');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
-- 
2.41.0.windows.3

From be09f442cdad02cdc458006e57a1e0d32b4d9129 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v20] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the object types to be removed from the subscriber.
This patch adds supports to specify 'publications' as an object type.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during physical replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  24 ++++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 108 +++++++++++++++---
 .../t/040_pg_createsubscriber.pl              |  25 +++-
 3 files changed, 142 insertions(+), 15 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..74b8424f555 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,30 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-r</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all objects of the specified type from specified databases on the
+       target server. Multiple object types can be specified by using multiple
+       <option>--remove</option> switches.
+      </para>
+      <para>
+       publications: The "all tables" publications established for this
+       subscriber are always removed; specifying this object type causes all
+       other publications replicated from the source server to be dropped as
+       well.
+      </para>
+      <para>
+       The objects selected to be dropped are individually logged and do show
+       up in a --dry-run.  There is no opportunity to affect or stop the
+       dropping of the selected objects so consider taking a backup of them
+       using pg_dump.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..4ea1310faee 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECTTYPE_PUBLICATIONS  0x1
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList objecttypes_to_remove; /* list of object types to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,8 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	bits32		objecttypes_to_remove;	/* flags indicating which object types
+										 * to remove on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -109,7 +113,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, const char *pubname,
+							 const char *dbname, bool *made_publication);
+static void check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +200,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+									 &dbinfo->made_publication);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +248,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -r, --remove=OBJECTTYPE         remove all objects of the specified type from specified\n"
+			 "                                  databases on the subscriber; accepts: publications\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1194,11 +1203,13 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publications were created before the consistent LSN, they
+		 * remain on the subscriber even after the physical replica is
+		 * promoted. Remove these publications from the subscriber because
+		 * they have no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		check_and_drop_publications(conn, &dbinfo[i]);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1663,10 +1674,11 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication in the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, const char *pubname, const char *dbname,
+				 bool *made_publication)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1686,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,8 +1703,8 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbname, PQresultErrorMessage(res));
+			*made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1708,6 +1720,45 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Check and drop the required publications in the given database.
+ */
+static void
+check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	Assert(conn != NULL);
+
+	if (dbinfos.objecttypes_to_remove & OBJECTTYPE_PUBLICATIONS)
+	{
+		pg_log_info("dropping all existing publications in database \"%s\"",
+					dbinfo->dbname);
+
+		/* Fetch all publication names */
+		res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
+			PQclear(res);
+			disconnect_database(conn, false);
+			return;
+		}
+
+		/* Drop each publication */
+		for (int i = 0; i < PQntuples(res); i++)
+			drop_publication(conn, PQgetvalue(res, i, 0), dbinfo->dbname,
+							 &dbinfo->made_publication);
+
+		PQclear(res);
+		pg_log_info("dropped all publications in database \"%s\"", dbinfo->dbname);
+	}
+	else
+		drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+						 &dbinfo->made_publication);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1965,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'r'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2047,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:r:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2077,17 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'r':
+				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
+				{
+					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
+				}
+				else
+				{
+					pg_log_error("object type \"%s\" is specified more than once for --remove", optarg);
+					exit(1);
+				}
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2252,25 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the object types specified for removal from the subscriber */
+	dbinfos.objecttypes_to_remove = 0x0;
+	if (opt.objecttypes_to_remove.head != NULL)
+	{
+		for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
+		{
+			if (pg_strcasecmp(cell->val, "publications") == 0)
+			{
+				dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
+			}
+			else
+			{
+				pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+				pg_log_error_hint("The valid option is: \"publications\"");
+				exit(1);
+			}
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..2c9bd5bdb9e 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two pre-existing publications on subscriber');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +388,8 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and
+# --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +405,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +425,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications on subscriber have been removed');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
-- 
2.41.0.windows.3

diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 4ea1310faee..d0e637d041f 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,7 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
-#define	OBJECTTYPE_PUBLICATIONS  0x1
+#define	OBJECTTYPE_PUBLICATIONS  0x0001
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -2079,9 +2079,7 @@ main(int argc, char **argv)
 				break;
 			case 'r':
 				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
-				{
 					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
-				}
 				else
 				{
 					pg_log_error("object type \"%s\" is specified more than once for --remove", optarg);
@@ -2253,15 +2251,12 @@ main(int argc, char **argv)
 	}
 
 	/* Verify the object types specified for removal from the subscriber */
-	dbinfos.objecttypes_to_remove = 0x0;
 	if (opt.objecttypes_to_remove.head != NULL)
 	{
 		for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
 		{
 			if (pg_strcasecmp(cell->val, "publications") == 0)
-			{
 				dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
-			}
 			else
 			{
 				pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);

From d8f5e910e8e816b2b6d9be18ef186fce8916308a Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v21] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the object types to be removed from the subscriber.
This patch adds supports to specify 'publications' as an object type.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during physical replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     |  24 ++++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 103 +++++++++++++++---
 .../t/040_pg_createsubscriber.pl              |  25 ++++-
 3 files changed, 137 insertions(+), 15 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..74b8424f555 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,30 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-r</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all objects of the specified type from specified databases on the
+       target server. Multiple object types can be specified by using multiple
+       <option>--remove</option> switches.
+      </para>
+      <para>
+       publications: The "all tables" publications established for this
+       subscriber are always removed; specifying this object type causes all
+       other publications replicated from the source server to be dropped as
+       well.
+      </para>
+      <para>
+       The objects selected to be dropped are individually logged and do show
+       up in a --dry-run.  There is no opportunity to affect or stop the
+       dropping of the selected objects so consider taking a backup of them
+       using pg_dump.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..d0e637d041f 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECTTYPE_PUBLICATIONS  0x0001
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList objecttypes_to_remove; /* list of object types to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,8 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	bits32		objecttypes_to_remove;	/* flags indicating which object types
+										 * to remove on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -109,7 +113,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, const char *pubname,
+							 const char *dbname, bool *made_publication);
+static void check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +200,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+									 &dbinfo->made_publication);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +248,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -r, --remove=OBJECTTYPE         remove all objects of the specified type from specified\n"
+			 "                                  databases on the subscriber; accepts: publications\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1194,11 +1203,13 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publications were created before the consistent LSN, they
+		 * remain on the subscriber even after the physical replica is
+		 * promoted. Remove these publications from the subscriber because
+		 * they have no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		check_and_drop_publications(conn, &dbinfo[i]);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1663,10 +1674,11 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication in the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, const char *pubname, const char *dbname,
+				 bool *made_publication)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1686,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,8 +1703,8 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbname, PQresultErrorMessage(res));
+			*made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1708,6 +1720,45 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Check and drop the required publications in the given database.
+ */
+static void
+check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	Assert(conn != NULL);
+
+	if (dbinfos.objecttypes_to_remove & OBJECTTYPE_PUBLICATIONS)
+	{
+		pg_log_info("dropping all existing publications in database \"%s\"",
+					dbinfo->dbname);
+
+		/* Fetch all publication names */
+		res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
+			PQclear(res);
+			disconnect_database(conn, false);
+			return;
+		}
+
+		/* Drop each publication */
+		for (int i = 0; i < PQntuples(res); i++)
+			drop_publication(conn, PQgetvalue(res, i, 0), dbinfo->dbname,
+							 &dbinfo->made_publication);
+
+		PQclear(res);
+		pg_log_info("dropped all publications in database \"%s\"", dbinfo->dbname);
+	}
+	else
+		drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+						 &dbinfo->made_publication);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1965,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'r'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2047,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:r:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2077,15 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'r':
+				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
+					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
+				else
+				{
+					pg_log_error("object type \"%s\" is specified more than once for --remove", optarg);
+					exit(1);
+				}
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2250,22 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the object types specified for removal from the subscriber */
+	if (opt.objecttypes_to_remove.head != NULL)
+	{
+		for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
+		{
+			if (pg_strcasecmp(cell->val, "publications") == 0)
+				dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
+			else
+			{
+				pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+				pg_log_error_hint("The valid option is: \"publications\"");
+				exit(1);
+			}
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..2c9bd5bdb9e 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two pre-existing publications on subscriber');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +388,8 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and
+# --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +405,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +425,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications on subscriber have been removed');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
-- 
2.41.0.windows.3

From ca4a2950ceb62709e5642eb2dbf05b08f4d2220d Mon Sep 17 00:00:00 2001
From: Hou Zhijie <houzj.fnst@cn.fujitsu.com>
Date: Wed, 19 Mar 2025 15:10:26 +0800
Subject: [PATCH] Some fixes

---
 src/bin/pg_basebackup/pg_createsubscriber.c | 26 +++++++--------------
 1 file changed, 9 insertions(+), 17 deletions(-)

diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index d0e637d041f..1d31a7ebae2 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -1742,8 +1742,7 @@ check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
 			pg_log_error("could not obtain publication information: %s",
 						 PQresultErrorMessage(res));
 			PQclear(res);
-			disconnect_database(conn, false);
-			return;
+			disconnect_database(conn, true);
 		}
 
 		/* Drop each publication */
@@ -1752,7 +1751,6 @@ check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
 							 &dbinfo->made_publication);
 
 		PQclear(res);
-		pg_log_info("dropped all publications in database \"%s\"", dbinfo->dbname);
 	}
 	else
 		drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
@@ -2081,10 +2079,7 @@ main(int argc, char **argv)
 				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
 					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
 				else
-				{
-					pg_log_error("object type \"%s\" is specified more than once for --remove", optarg);
-					exit(1);
-				}
+					pg_fatal("object type \"%s\" is specified more than once for --remove", optarg);
 				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
@@ -2251,18 +2246,15 @@ main(int argc, char **argv)
 	}
 
 	/* Verify the object types specified for removal from the subscriber */
-	if (opt.objecttypes_to_remove.head != NULL)
+	for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
 	{
-		for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
+		if (pg_strcasecmp(cell->val, "publications") == 0)
+			dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
+		else
 		{
-			if (pg_strcasecmp(cell->val, "publications") == 0)
-				dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
-			else
-			{
-				pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
-				pg_log_error_hint("The valid option is: \"publications\"");
-				exit(1);
-			}
+			pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+			pg_log_error_hint("The valid option is: \"publications\"");
+			exit(1);
 		}
 	}
 
-- 
2.30.0.windows.2

From 902ad8ebad0f490bcc00be04a073713902402a58 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v22] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the object types to be removed from the subscriber.
This patch adds supports to specify 'publications' as an object type.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during physical replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     | 24 +++++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 95 ++++++++++++++++---
 .../t/040_pg_createsubscriber.pl              | 25 ++++-
 3 files changed, 129 insertions(+), 15 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..74b8424f555 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,30 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-r</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all objects of the specified type from specified databases on the
+       target server. Multiple object types can be specified by using multiple
+       <option>--remove</option> switches.
+      </para>
+      <para>
+       publications: The "all tables" publications established for this
+       subscriber are always removed; specifying this object type causes all
+       other publications replicated from the source server to be dropped as
+       well.
+      </para>
+      <para>
+       The objects selected to be dropped are individually logged and do show
+       up in a --dry-run.  There is no opportunity to affect or stop the
+       dropping of the selected objects so consider taking a backup of them
+       using pg_dump.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..1d31a7ebae2 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECTTYPE_PUBLICATIONS  0x0001
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList objecttypes_to_remove; /* list of object types to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,8 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	bits32		objecttypes_to_remove;	/* flags indicating which object types
+										 * to remove on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -109,7 +113,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, const char *pubname,
+							 const char *dbname, bool *made_publication);
+static void check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +200,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+									 &dbinfo->made_publication);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +248,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -r, --remove=OBJECTTYPE         remove all objects of the specified type from specified\n"
+			 "                                  databases on the subscriber; accepts: publications\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1194,11 +1203,13 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publications were created before the consistent LSN, they
+		 * remain on the subscriber even after the physical replica is
+		 * promoted. Remove these publications from the subscriber because
+		 * they have no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		check_and_drop_publications(conn, &dbinfo[i]);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1663,10 +1674,11 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication in the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, const char *pubname, const char *dbname,
+				 bool *made_publication)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1686,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,8 +1703,8 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbname, PQresultErrorMessage(res));
+			*made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1708,6 +1720,43 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Check and drop the required publications in the given database.
+ */
+static void
+check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	Assert(conn != NULL);
+
+	if (dbinfos.objecttypes_to_remove & OBJECTTYPE_PUBLICATIONS)
+	{
+		pg_log_info("dropping all existing publications in database \"%s\"",
+					dbinfo->dbname);
+
+		/* Fetch all publication names */
+		res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
+			PQclear(res);
+			disconnect_database(conn, true);
+		}
+
+		/* Drop each publication */
+		for (int i = 0; i < PQntuples(res); i++)
+			drop_publication(conn, PQgetvalue(res, i, 0), dbinfo->dbname,
+							 &dbinfo->made_publication);
+
+		PQclear(res);
+	}
+	else
+		drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+						 &dbinfo->made_publication);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1963,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'r'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2045,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:r:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2075,12 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'r':
+				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
+					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
+				else
+					pg_fatal("object type \"%s\" is specified more than once for --remove", optarg);
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2245,19 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the object types specified for removal from the subscriber */
+	for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
+	{
+		if (pg_strcasecmp(cell->val, "publications") == 0)
+			dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
+		else
+		{
+			pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+			pg_log_error_hint("The valid option is: \"publications\"");
+			exit(1);
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..2c9bd5bdb9e 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two pre-existing publications on subscriber');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +388,8 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and
+# --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +405,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +425,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications on subscriber have been removed');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
-- 
2.41.0.windows.3

From 19fad9d2decc5576cbecb678af30ae4852510a81 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v23] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the object types to be removed from the subscriber.
This patch adds supports to specify 'publications' as an object type.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during physical replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     | 24 +++++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 95 ++++++++++++++++---
 .../t/040_pg_createsubscriber.pl              | 25 ++++-
 3 files changed, 129 insertions(+), 15 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..4fe3ff75a81 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,30 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-R</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all objects of the specified type from specified databases on the
+       target server. Multiple object types can be specified by using multiple
+       <option>--remove</option> switches.
+      </para>
+      <para>
+       publications: The "all tables" publications established for this
+       subscriber are always removed; specifying this object type causes all
+       other publications replicated from the source server to be dropped as
+       well.
+      </para>
+      <para>
+       The objects selected to be dropped are individually logged and do show
+       up in a --dry-run.  There is no opportunity to affect or stop the
+       dropping of the selected objects so consider taking a backup of them
+       using pg_dump.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..ba16aff32b6 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECTTYPE_PUBLICATIONS  0x0001
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList objecttypes_to_remove; /* list of object types to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,8 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	bits32		objecttypes_to_remove;	/* flags indicating which object types
+										 * to remove on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -109,7 +113,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, const char *pubname,
+							 const char *dbname, bool *made_publication);
+static void check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +200,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+									 &dbinfo->made_publication);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +248,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -R, --remove=OBJECTTYPE         remove all objects of the specified type from specified\n"
+			 "                                  databases on the subscriber; accepts: publications\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1194,11 +1203,13 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
 		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
+		 * Since the publications were created before the consistent LSN, they
+		 * remain on the subscriber even after the physical replica is
+		 * promoted. Remove these publications from the subscriber because
+		 * they have no use. Additionally, if requested, drop all pre-existing
+		 * publications.
 		 */
-		drop_publication(conn, &dbinfo[i]);
+		check_and_drop_publications(conn, &dbinfo[i]);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1663,10 +1674,11 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication in the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, const char *pubname, const char *dbname,
+				 bool *made_publication)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1686,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,8 +1703,8 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbname, PQresultErrorMessage(res));
+			*made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1708,6 +1720,43 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Check and drop the required publications in the given database.
+ */
+static void
+check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	Assert(conn != NULL);
+
+	if (dbinfos.objecttypes_to_remove & OBJECTTYPE_PUBLICATIONS)
+	{
+		pg_log_info("dropping all existing publications in database \"%s\"",
+					dbinfo->dbname);
+
+		/* Fetch all publication names */
+		res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
+			PQclear(res);
+			disconnect_database(conn, true);
+		}
+
+		/* Drop each publication */
+		for (int i = 0; i < PQntuples(res); i++)
+			drop_publication(conn, PQgetvalue(res, i, 0), dbinfo->dbname,
+							 &dbinfo->made_publication);
+
+		PQclear(res);
+	}
+	else
+		drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+						 &dbinfo->made_publication);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1963,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'R'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2045,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:R:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2075,12 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'R':
+				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
+					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
+				else
+					pg_fatal("object type \"%s\" is specified more than once for --remove", optarg);
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2245,19 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the object types specified for removal from the subscriber */
+	for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
+	{
+		if (pg_strcasecmp(cell->val, "publications") == 0)
+			dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
+		else
+		{
+			pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+			pg_log_error_hint("The valid option is: \"publications\"");
+			exit(1);
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..2c9bd5bdb9e 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two pre-existing publications on subscriber');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +388,8 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and
+# --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +405,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +425,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications on subscriber have been removed');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
-- 
2.41.0.windows.3

From 4b03e44138fbbec3892b5f4eb55c9e798eba71f5 Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v24] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the object types to be removed from the subscriber.
This patch adds supports to specify 'publications' as an object type.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during physical replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     | 23 +++++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 99 ++++++++++++++++---
 .../t/040_pg_createsubscriber.pl              | 25 ++++-
 3 files changed, 130 insertions(+), 17 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..380d0b1c35c 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,29 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-R</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all objects of the specified type from specified databases on the
+       target server.
+      </para>
+      <para>
+       publications: The "all tables" publications established for this
+       subscriber are always removed; specifying this object type causes all
+       other publications replicated from the source server to be dropped as
+       well.
+      </para>
+      <para>
+       The objects selected to be dropped are individually logged and do show
+       up in a --dry-run.  There is no opportunity to affect or stop the
+       dropping of the selected objects so consider taking a backup of them
+       using pg_dump.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..11e66c7831d 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECTTYPE_PUBLICATIONS  0x0001
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList objecttypes_to_remove; /* list of object types to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,8 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	bits32		objecttypes_to_remove;	/* flags indicating which object types
+										 * to remove on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -109,7 +113,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, const char *pubname,
+							 const char *dbname, bool *made_publication);
+static void check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +200,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+									 &dbinfo->made_publication);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +248,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -R, --remove=OBJECTTYPE         remove all objects of the specified type from specified\n"
+			 "                                  databases on the subscriber; accepts: publications\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1193,12 +1202,8 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 */
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
-		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
-		 */
-		drop_publication(conn, &dbinfo[i]);
+		/* Check and drop the required publications in the given database. */
+		check_and_drop_publications(conn, &dbinfo[i]);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1663,10 +1668,11 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication in the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, const char *pubname, const char *dbname,
+				 bool *made_publication)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1680,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,8 +1697,8 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbname, PQresultErrorMessage(res));
+			*made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1708,6 +1714,49 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Retrieve and drop the publications.
+ *
+ * Since the publications were created before the consistent LSN, they
+ * remain on the subscriber even after the physical replica is
+ * promoted. Remove these publications from the subscriber because
+ * they have no use. Additionally, if requested, drop all pre-existing
+ * publications.
+ */
+static void
+check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	Assert(conn != NULL);
+
+	if (dbinfos.objecttypes_to_remove & OBJECTTYPE_PUBLICATIONS)
+	{
+		pg_log_info("dropping all existing publications in database \"%s\"",
+					dbinfo->dbname);
+
+		/* Fetch all publication names */
+		res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
+			PQclear(res);
+			disconnect_database(conn, true);
+		}
+
+		/* Drop each publication */
+		for (int i = 0; i < PQntuples(res); i++)
+			drop_publication(conn, PQgetvalue(res, i, 0), dbinfo->dbname,
+							 &dbinfo->made_publication);
+
+		PQclear(res);
+	}
+	else
+		drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+						 &dbinfo->made_publication);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1963,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'R'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2045,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:R:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2075,12 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'R':
+				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
+					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
+				else
+					pg_fatal("object type \"%s\" is specified more than once for --remove", optarg);
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2245,19 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the object types specified for removal from the subscriber */
+	for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
+	{
+		if (pg_strcasecmp(cell->val, "publications") == 0)
+			dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
+		else
+		{
+			pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+			pg_log_error_hint("The valid option is: \"publications\"");
+			exit(1);
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..2c9bd5bdb9e 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,21 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove'
+# removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two pre-existing publications on subscriber');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +388,8 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and
+# --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +405,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +425,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications on subscriber have been removed');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
-- 
2.41.0.windows.3

From 82c3496503b7e69ba9b98389c15d10075885bb8f Mon Sep 17 00:00:00 2001
From: Khanna <Shubham.Khanna@fujitsu.com>
Date: Mon, 17 Mar 2025 09:07:37 +0530
Subject: [PATCH v25] Support for dropping all publications in
 'pg_createsubscriber'

This patch introduces a new '--remove' option in the 'pg_createsubscriber'
utility to specify the object types to be removed from the subscriber.
This patch adds supports to specify 'publications' as an object type.

This feature ensures a clean and streamlined setup of logical replication by
removing publications on the subscriber that were originally replicated from
the primary server during physical replication.
These publications become redundant once the setup transitions to logical
replication and serve no further purpose.

This cleanup process removes all publications from the subscriber, regardless
of their origin.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     | 23 +++++
 src/bin/pg_basebackup/pg_createsubscriber.c   | 99 ++++++++++++++++---
 .../t/040_pg_createsubscriber.pl              | 23 ++++-
 3 files changed, 128 insertions(+), 17 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index b4b996236e4..380d0b1c35c 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -146,6 +146,29 @@ PostgreSQL documentation
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>-R</option></term>
+     <term><option>--remove</option></term>
+     <listitem>
+      <para>
+       Remove all objects of the specified type from specified databases on the
+       target server.
+      </para>
+      <para>
+       publications: The "all tables" publications established for this
+       subscriber are always removed; specifying this object type causes all
+       other publications replicated from the source server to be dropped as
+       well.
+      </para>
+      <para>
+       The objects selected to be dropped are individually logged and do show
+       up in a --dry-run.  There is no opportunity to affect or stop the
+       dropping of the selected objects so consider taking a backup of them
+       using pg_dump.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index 6baf92e8024..11e66c7831d 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -29,6 +29,7 @@
 #include "getopt_long.h"
 
 #define	DEFAULT_SUB_PORT	"50432"
+#define	OBJECTTYPE_PUBLICATIONS  0x0001
 
 /* Command-line options */
 struct CreateSubscriberOptions
@@ -44,6 +45,7 @@ struct CreateSubscriberOptions
 	SimpleStringList sub_names; /* list of subscription names */
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
+	SimpleStringList objecttypes_to_remove; /* list of object types to remove */
 };
 
 /* per-database publication/subscription info */
@@ -68,6 +70,8 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
+	bits32		objecttypes_to_remove;	/* flags indicating which object types
+										 * to remove on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -109,7 +113,9 @@ static void stop_standby_server(const char *datadir);
 static void wait_for_end_recovery(const char *conninfo,
 								  const struct CreateSubscriberOptions *opt);
 static void create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
-static void drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo);
+static void drop_publication(PGconn *conn, const char *pubname,
+							 const char *dbname, bool *made_publication);
+static void check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo);
 static void create_subscription(PGconn *conn, const struct LogicalRepInfo *dbinfo);
 static void set_replication_progress(PGconn *conn, const struct LogicalRepInfo *dbinfo,
 									 const char *lsn);
@@ -194,7 +200,8 @@ cleanup_objects_atexit(void)
 			if (conn != NULL)
 			{
 				if (dbinfo->made_publication)
-					drop_publication(conn, dbinfo);
+					drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+									 &dbinfo->made_publication);
 				if (dbinfo->made_replslot)
 					drop_replication_slot(conn, dbinfo, dbinfo->replslotname);
 				disconnect_database(conn, false);
@@ -241,6 +248,8 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
+	printf(_("  -R, --remove=OBJECTTYPE         remove all objects of the specified type from specified\n"
+			 "                                  databases on the subscriber; accepts: publications\n"));
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
@@ -1193,12 +1202,8 @@ setup_subscriber(struct LogicalRepInfo *dbinfo, const char *consistent_lsn)
 		 */
 		check_and_drop_existing_subscriptions(conn, &dbinfo[i]);
 
-		/*
-		 * Since the publication was created before the consistent LSN, it is
-		 * available on the subscriber when the physical replica is promoted.
-		 * Remove publications from the subscriber because it has no use.
-		 */
-		drop_publication(conn, &dbinfo[i]);
+		/* Check and drop the required publications in the given database. */
+		check_and_drop_publications(conn, &dbinfo[i]);
 
 		create_subscription(conn, &dbinfo[i]);
 
@@ -1663,10 +1668,11 @@ create_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 }
 
 /*
- * Remove publication if it couldn't finish all steps.
+ * Drop the specified publication in the given database.
  */
 static void
-drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
+drop_publication(PGconn *conn, const char *pubname, const char *dbname,
+				 bool *made_publication)
 {
 	PQExpBuffer str = createPQExpBuffer();
 	PGresult   *res;
@@ -1674,10 +1680,10 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 
 	Assert(conn != NULL);
 
-	pubname_esc = PQescapeIdentifier(conn, dbinfo->pubname, strlen(dbinfo->pubname));
+	pubname_esc = PQescapeIdentifier(conn, pubname, strlen(pubname));
 
 	pg_log_info("dropping publication \"%s\" in database \"%s\"",
-				dbinfo->pubname, dbinfo->dbname);
+				pubname, dbname);
 
 	appendPQExpBuffer(str, "DROP PUBLICATION %s", pubname_esc);
 
@@ -1691,8 +1697,8 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 		if (PQresultStatus(res) != PGRES_COMMAND_OK)
 		{
 			pg_log_error("could not drop publication \"%s\" in database \"%s\": %s",
-						 dbinfo->pubname, dbinfo->dbname, PQresultErrorMessage(res));
-			dbinfo->made_publication = false;	/* don't try again. */
+						 pubname, dbname, PQresultErrorMessage(res));
+			*made_publication = false;	/* don't try again. */
 
 			/*
 			 * Don't disconnect and exit here. This routine is used by primary
@@ -1708,6 +1714,49 @@ drop_publication(PGconn *conn, struct LogicalRepInfo *dbinfo)
 	destroyPQExpBuffer(str);
 }
 
+/*
+ * Retrieve and drop the publications.
+ *
+ * Since the publications were created before the consistent LSN, they
+ * remain on the subscriber even after the physical replica is
+ * promoted. Remove these publications from the subscriber because
+ * they have no use. Additionally, if requested, drop all pre-existing
+ * publications.
+ */
+static void
+check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
+{
+	PGresult   *res;
+
+	Assert(conn != NULL);
+
+	if (dbinfos.objecttypes_to_remove & OBJECTTYPE_PUBLICATIONS)
+	{
+		pg_log_info("dropping all existing publications in database \"%s\"",
+					dbinfo->dbname);
+
+		/* Fetch all publication names */
+		res = PQexec(conn, "SELECT pubname FROM pg_catalog.pg_publication;");
+		if (PQresultStatus(res) != PGRES_TUPLES_OK)
+		{
+			pg_log_error("could not obtain publication information: %s",
+						 PQresultErrorMessage(res));
+			PQclear(res);
+			disconnect_database(conn, true);
+		}
+
+		/* Drop each publication */
+		for (int i = 0; i < PQntuples(res); i++)
+			drop_publication(conn, PQgetvalue(res, i, 0), dbinfo->dbname,
+							 &dbinfo->made_publication);
+
+		PQclear(res);
+	}
+	else
+		drop_publication(conn, dbinfo->pubname, dbinfo->dbname,
+						 &dbinfo->made_publication);
+}
+
 /*
  * Create a subscription with some predefined options.
  *
@@ -1914,6 +1963,7 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
+		{"remove", required_argument, NULL, 'R'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -1995,7 +2045,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "d:D:np:P:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "d:D:np:P:R:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2025,6 +2075,12 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
+			case 'R':
+				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
+					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
+				else
+					pg_fatal("object type \"%s\" is specified more than once for --remove", optarg);
+				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2189,6 +2245,19 @@ main(int argc, char **argv)
 		exit(1);
 	}
 
+	/* Verify the object types specified for removal from the subscriber */
+	for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
+	{
+		if (pg_strcasecmp(cell->val, "publications") == 0)
+			dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
+		else
+		{
+			pg_log_error("invalid object type \"%s\" specified for --remove", cell->val);
+			pg_log_error_hint("The valid option is: \"publications\"");
+			exit(1);
+		}
+	}
+
 	/* Get the absolute path of pg_ctl and pg_resetwal on the subscriber */
 	pg_ctl_path = get_exec_path(argv[0], "pg_ctl");
 	pg_resetwal_path = get_exec_path(argv[0], "pg_resetwal");
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index c35fa108ce3..88d8811646b 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -329,6 +329,20 @@ $node_p->safe_psql($db1,
 	"CREATE SUBSCRIPTION $dummy_sub CONNECTION 'dbname=dummy' PUBLICATION pub_dummy WITH (connect=false)"
 );
 $node_p->wait_for_replay_catchup($node_s);
+
+# Create user-defined publications, wait for streaming replication to sync them
+# to the standby, then verify that '--remove' removes them.
+$node_p->safe_psql(
+	$db1, qq(
+	CREATE PUBLICATION test_pub1 FOR ALL TABLES;
+	CREATE PUBLICATION test_pub2 FOR ALL TABLES;
+));
+
+$node_p->wait_for_replay_catchup($node_s);
+
+ok($node_s->safe_psql($db1, "SELECT COUNT(*) = 2 FROM pg_publication"),
+	'two pre-existing publications on subscriber');
+
 $node_s->stop;
 
 # dry run mode on node S
@@ -373,7 +387,7 @@ command_ok(
 
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
-# In passing, also test the --enable-two-phase option
+# In passing, also test the --enable-two-phase option and --remove option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -389,7 +403,8 @@ command_ok(
 		'--replication-slot' => 'replslot2',
 		'--database' => $db1,
 		'--database' => $db2,
-		'--enable-two-phase'
+		'--enable-two-phase',
+		'--remove' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
@@ -408,6 +423,10 @@ $node_p->safe_psql($db2, "INSERT INTO tbl2 VALUES('row 1')");
 # Start subscriber
 $node_s->start;
 
+# Confirm publications are removed from the subscriber node
+is($node_s->safe_psql($db1, "SELECT COUNT(*) FROM pg_publication;"),
+	'0', 'all publications on subscriber have been removed');
+
 # Verify that all subtwophase states are pending or enabled,
 # e.g. there are no subscriptions where subtwophase is disabled ('d')
 is( $node_s->safe_psql(
-- 
2.41.0.windows.3

From 0b2b7fe187f2216b4cd5a8fea3828d9e0b37e4bd Mon Sep 17 00:00:00 2001
From: Peter Smith <peter.b.smith@fujitsu.com>
Date: Thu, 3 Apr 2025 14:19:51 +1100
Subject: [PATCH v1] improvements for --remove option documentation

---
 doc/src/sgml/ref/pg_createsubscriber.sgml | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index 1f0ddd7..73377aa 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -167,24 +167,31 @@ PostgreSQL documentation
     </varlistentry>
 
     <varlistentry>
-     <term><option>-R</option></term>
-     <term><option>--remove</option></term>
+     <term><option>-R <replaceable class="parameter">objtype</replaceable></option></term>
+     <term><option>--remove=<replaceable class="parameter">objtype</replaceable></option></term>
      <listitem>
       <para>
        Remove all objects of the specified type from specified databases on the
        target server.
       </para>
       <para>
-       publications: The "all tables" publications established for this
-       subscriber are always removed; specifying this object type causes all
-       other publications replicated from the source server to be dropped as
-       well.
+       <itemizedlist>
+        <listitem>
+         <para>
+          <literal>publications</literal>:
+          The <literal>FOR ALL TABLES</literal> publications established for this
+          subscriber are always removed; specifying this object type causes all
+          other publications replicated from the source server to be dropped as
+          well.
+         </para>
+        </listitem>
+       </itemizedlist>
       </para>
       <para>
-       The objects selected to be dropped are individually logged and do show
-       up in a --dry-run.  There is no opportunity to affect or stop the
-       dropping of the selected objects so consider taking a backup of them
-       using pg_dump.
+       The objects selected to be dropped are individually logged, including during
+       a <option>--dry-run</option>.  There is no opportunity to affect or stop the
+       dropping of the selected objects, so consider taking a backup of them
+       using <application>pg_dump</application>.
       </para>
      </listitem>
     </varlistentry>
-- 
1.8.3.1

From ca732064488a712fed58f362e1033e119a591b99 Mon Sep 17 00:00:00 2001
From: Peter Eisentraut <peter@eisentraut.org>
Date: Sun, 22 Jun 2025 17:42:29 +0200
Subject: [PATCH] pg_createsubscriber: Rename option --remove to --clean

After discussion, the name --remove was suboptimally chosen.  --clean
has more precedent in other PostgreSQL tools.
---
 doc/src/sgml/ref/pg_createsubscriber.sgml     | 59 +++++++++----------
 src/bin/pg_basebackup/pg_createsubscriber.c   | 34 +++++------
 .../t/040_pg_createsubscriber.pl              |  6 +-
 3 files changed, 49 insertions(+), 50 deletions(-)

diff --git a/doc/src/sgml/ref/pg_createsubscriber.sgml b/doc/src/sgml/ref/pg_createsubscriber.sgml
index 4b1d08d5f16..bb9cc72576c 100644
--- a/doc/src/sgml/ref/pg_createsubscriber.sgml
+++ b/doc/src/sgml/ref/pg_createsubscriber.sgml
@@ -169,36 +169,6 @@ <title>Options</title>
      </listitem>
     </varlistentry>
 
-    <varlistentry>
-     <term><option>-R <replaceable class="parameter">objtype</replaceable></option></term>
-     <term><option>--remove=<replaceable class="parameter">objtype</replaceable></option></term>
-     <listitem>
-      <para>
-       Remove all objects of the specified type from specified databases on the
-       target server.
-      </para>
-      <para>
-       <itemizedlist>
-        <listitem>
-         <para>
-          <literal>publications</literal>:
-          The <literal>FOR ALL TABLES</literal> publications established for this
-          subscriber are always removed; specifying this object type causes all
-          other publications replicated from the source server to be dropped as
-          well.
-         </para>
-        </listitem>
-       </itemizedlist>
-      </para>
-      <para>
-       The objects selected to be dropped are individually logged, including during
-       a <option>--dry-run</option>.  There is no opportunity to affect or stop the
-       dropping of the selected objects, so consider taking a backup of them
-       using <application>pg_dump</application>.
-      </para>
-     </listitem>
-    </varlistentry>
-
     <varlistentry>
      <term><option>-s <replaceable class="parameter">dir</replaceable></option></term>
      <term><option>--socketdir=<replaceable class="parameter">dir</replaceable></option></term>
@@ -259,6 +229,35 @@ <title>Options</title>
      </listitem>
     </varlistentry>
 
+    <varlistentry>
+     <term><option>--clean=<replaceable class="parameter">objtype</replaceable></option></term>
+     <listitem>
+      <para>
+       Drop all objects of the specified type from specified databases on the
+       target server.
+      </para>
+      <para>
+       <itemizedlist>
+        <listitem>
+         <para>
+          <literal>publications</literal>:
+          The <literal>FOR ALL TABLES</literal> publications established for this
+          subscriber are always dropped; specifying this object type causes all
+          other publications replicated from the source server to be dropped as
+          well.
+         </para>
+        </listitem>
+       </itemizedlist>
+      </para>
+      <para>
+       The objects selected to be dropped are individually logged, including during
+       a <option>--dry-run</option>.  There is no opportunity to affect or stop the
+       dropping of the selected objects, so consider taking a backup of them
+       using <application>pg_dump</application>.
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry>
      <term><option>--config-file=<replaceable class="parameter">filename</replaceable></option></term>
      <listitem>
diff --git a/src/bin/pg_basebackup/pg_createsubscriber.c b/src/bin/pg_basebackup/pg_createsubscriber.c
index c43c0cbbba5..11f71c03801 100644
--- a/src/bin/pg_basebackup/pg_createsubscriber.c
+++ b/src/bin/pg_basebackup/pg_createsubscriber.c
@@ -46,7 +46,7 @@ struct CreateSubscriberOptions
 	SimpleStringList replslot_names;	/* list of replication slot names */
 	int			recovery_timeout;	/* stop recovery after this time */
 	bool		all_dbs;		/* all option */
-	SimpleStringList objecttypes_to_remove; /* list of object types to remove */
+	SimpleStringList objecttypes_to_clean;	/* list of object types to cleanup */
 };
 
 /* per-database publication/subscription info */
@@ -71,8 +71,8 @@ struct LogicalRepInfos
 {
 	struct LogicalRepInfo *dbinfo;
 	bool		two_phase;		/* enable-two-phase option */
-	bits32		objecttypes_to_remove;	/* flags indicating which object types
-										 * to remove on subscriber */
+	bits32		objecttypes_to_clean;	/* flags indicating which object types
+										 * to clean up on subscriber */
 };
 
 static void cleanup_objects_atexit(void);
@@ -253,13 +253,13 @@ usage(void)
 	printf(_("  -n, --dry-run                   dry run, just show what would be done\n"));
 	printf(_("  -p, --subscriber-port=PORT      subscriber port number (default %s)\n"), DEFAULT_SUB_PORT);
 	printf(_("  -P, --publisher-server=CONNSTR  publisher connection string\n"));
-	printf(_("  -R, --remove=OBJECTTYPE         remove all objects of the specified type from specified\n"
-			 "                                  databases on the subscriber; accepts: \"%s\"\n"), "publications");
 	printf(_("  -s, --socketdir=DIR             socket directory to use (default current dir.)\n"));
 	printf(_("  -t, --recovery-timeout=SECS     seconds to wait for recovery to end\n"));
 	printf(_("  -T, --enable-two-phase          enable two-phase commit for all subscriptions\n"));
 	printf(_("  -U, --subscriber-username=NAME  user name for subscriber connection\n"));
 	printf(_("  -v, --verbose                   output verbose messages\n"));
+	printf(_("      --clean=OBJECTTYPE          drop all objects of the specified type from specified\n"
+			 "                                  databases on the subscriber; accepts: \"%s\"\n"), "publications");
 	printf(_("      --config-file=FILENAME      use specified main server configuration\n"
 			 "                                  file when running target cluster\n"));
 	printf(_("      --publication=NAME          publication name\n"));
@@ -1730,7 +1730,7 @@ static void
 check_and_drop_publications(PGconn *conn, struct LogicalRepInfo *dbinfo)
 {
 	PGresult   *res;
-	bool		drop_all_pubs = dbinfos.objecttypes_to_remove & OBJECTTYPE_PUBLICATIONS;
+	bool		drop_all_pubs = dbinfos.objecttypes_to_clean & OBJECTTYPE_PUBLICATIONS;
 
 	Assert(conn != NULL);
 
@@ -2026,7 +2026,6 @@ main(int argc, char **argv)
 		{"dry-run", no_argument, NULL, 'n'},
 		{"subscriber-port", required_argument, NULL, 'p'},
 		{"publisher-server", required_argument, NULL, 'P'},
-		{"remove", required_argument, NULL, 'R'},
 		{"socketdir", required_argument, NULL, 's'},
 		{"recovery-timeout", required_argument, NULL, 't'},
 		{"enable-two-phase", no_argument, NULL, 'T'},
@@ -2038,6 +2037,7 @@ main(int argc, char **argv)
 		{"publication", required_argument, NULL, 2},
 		{"replication-slot", required_argument, NULL, 3},
 		{"subscription", required_argument, NULL, 4},
+		{"clean", required_argument, NULL, 5},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -2109,7 +2109,7 @@ main(int argc, char **argv)
 
 	get_restricted_token();
 
-	while ((c = getopt_long(argc, argv, "ad:D:np:P:R:s:t:TU:v",
+	while ((c = getopt_long(argc, argv, "ad:D:np:P:s:t:TU:v",
 							long_options, &option_index)) != -1)
 	{
 		switch (c)
@@ -2139,12 +2139,6 @@ main(int argc, char **argv)
 			case 'P':
 				opt.pub_conninfo_str = pg_strdup(optarg);
 				break;
-			case 'R':
-				if (!simple_string_list_member(&opt.objecttypes_to_remove, optarg))
-					simple_string_list_append(&opt.objecttypes_to_remove, optarg);
-				else
-					pg_fatal("object type \"%s\" specified more than once for -R/--remove", optarg);
-				break;
 			case 's':
 				opt.socket_dir = pg_strdup(optarg);
 				canonicalize_path(opt.socket_dir);
@@ -2191,6 +2185,12 @@ main(int argc, char **argv)
 				else
 					pg_fatal("subscription \"%s\" specified more than once for --subscription", optarg);
 				break;
+			case 5:
+				if (!simple_string_list_member(&opt.objecttypes_to_clean, optarg))
+					simple_string_list_append(&opt.objecttypes_to_clean, optarg);
+				else
+					pg_fatal("object type \"%s\" specified more than once for --clean", optarg);
+				break;
 			default:
 				/* getopt_long already emitted a complaint */
 				pg_log_error_hint("Try \"%s --help\" for more information.", progname);
@@ -2334,13 +2334,13 @@ main(int argc, char **argv)
 	}
 
 	/* Verify the object types specified for removal from the subscriber */
-	for (SimpleStringListCell *cell = opt.objecttypes_to_remove.head; cell; cell = cell->next)
+	for (SimpleStringListCell *cell = opt.objecttypes_to_clean.head; cell; cell = cell->next)
 	{
 		if (pg_strcasecmp(cell->val, "publications") == 0)
-			dbinfos.objecttypes_to_remove |= OBJECTTYPE_PUBLICATIONS;
+			dbinfos.objecttypes_to_clean |= OBJECTTYPE_PUBLICATIONS;
 		else
 		{
-			pg_log_error("invalid object type \"%s\" specified for -R/--remove", cell->val);
+			pg_log_error("invalid object type \"%s\" specified for --clean", cell->val);
 			pg_log_error_hint("The valid value is: \"%s\"", "publications");
 			exit(1);
 		}
diff --git a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
index df4924023fd..229fef5b3b5 100644
--- a/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
+++ b/src/bin/pg_basebackup/t/040_pg_createsubscriber.pl
@@ -331,7 +331,7 @@ sub generate_db
 $node_p->wait_for_replay_catchup($node_s);
 
 # Create user-defined publications, wait for streaming replication to sync them
-# to the standby, then verify that '--remove'
+# to the standby, then verify that '--clean'
 # removes them.
 $node_p->safe_psql(
 	$db1, qq(
@@ -446,7 +446,7 @@ sub generate_db
 # Run pg_createsubscriber on node S.  --verbose is used twice
 # to show more information.
 # In passing, also test the --enable-two-phase option and
-# --remove option
+# --clean option
 command_ok(
 	[
 		'pg_createsubscriber',
@@ -463,7 +463,7 @@ sub generate_db
 		'--database' => $db1,
 		'--database' => $db2,
 		'--enable-two-phase',
-		'--remove' => 'publications',
+		'--clean' => 'publications',
 	],
 	'run pg_createsubscriber on node S');
 
-- 
2.50.0