From 6fe675dbe236d6fae1fbd2ec0b1f9b83607014e9 Mon Sep 17 00:00:00 2001
From: Julien Rouhaud <julien.rouhaud@free.fr>
Date: Thu, 25 Feb 2021 01:33:58 +0800
Subject: [PATCH v6 2/2] Add a --outdated option to reindexdb

This uses the new OUTDATED option for REINDEX.  If user asks for multiple job,
the list of tables to process will be sorted by the total size of underlying
indexes that have outdated dependency.

Author: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by:
Discussion: https://postgr.es/m/20201203093143.GA64934%40nol
---
 src/bin/scripts/reindexdb.c        | 143 ++++++++++++++++++++++++-----
 src/bin/scripts/t/090_reindexdb.pl |  34 ++++++-
 2 files changed, 151 insertions(+), 26 deletions(-)

diff --git a/src/bin/scripts/reindexdb.c b/src/bin/scripts/reindexdb.c
index fc0681538a..addea5c1ed 100644
--- a/src/bin/scripts/reindexdb.c
+++ b/src/bin/scripts/reindexdb.c
@@ -35,20 +35,23 @@ typedef enum ReindexType
 static SimpleStringList *get_parallel_object_list(PGconn *conn,
 												  ReindexType type,
 												  SimpleStringList *user_list,
+												  bool outdated,
 												  bool echo);
 static void reindex_one_database(ConnParams *cparams, ReindexType type,
 								 SimpleStringList *user_list,
 								 const char *progname,
 								 bool echo, bool verbose, bool concurrently,
-								 int concurrentCons, const char *tablespace);
+								 int concurrentCons, const char *tablespace,
+								 bool outdated);
 static void reindex_all_databases(ConnParams *cparams,
 								  const char *progname, bool echo,
 								  bool quiet, bool verbose, bool concurrently,
-								  int concurrentCons, const char *tablespace);
+								  int concurrentCons, const char *tablespace,
+								  bool outdated);
 static void run_reindex_command(PGconn *conn, ReindexType type,
 								const char *name, bool echo, bool verbose,
 								bool concurrently, bool async,
-								const char *tablespace);
+								const char *tablespace, bool outdated);
 
 static void help(const char *progname);
 
@@ -74,6 +77,7 @@ main(int argc, char *argv[])
 		{"concurrently", no_argument, NULL, 1},
 		{"maintenance-db", required_argument, NULL, 2},
 		{"tablespace", required_argument, NULL, 3},
+		{"outdated", no_argument, NULL, 4},
 		{NULL, 0, NULL, 0}
 	};
 
@@ -95,6 +99,7 @@ main(int argc, char *argv[])
 	bool		quiet = false;
 	bool		verbose = false;
 	bool		concurrently = false;
+	bool		outdated = false;
 	SimpleStringList indexes = {NULL, NULL};
 	SimpleStringList tables = {NULL, NULL};
 	SimpleStringList schemas = {NULL, NULL};
@@ -170,6 +175,9 @@ main(int argc, char *argv[])
 			case 3:
 				tablespace = pg_strdup(optarg);
 				break;
+			case 4:
+				outdated = true;
+				break;
 			default:
 				fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
 				exit(1);
@@ -234,7 +242,8 @@ main(int argc, char *argv[])
 		cparams.dbname = maintenance_db;
 
 		reindex_all_databases(&cparams, progname, echo, quiet, verbose,
-							  concurrently, concurrentCons, tablespace);
+							  concurrently, concurrentCons, tablespace,
+							  outdated);
 	}
 	else if (syscatalog)
 	{
@@ -253,12 +262,17 @@ main(int argc, char *argv[])
 			pg_log_error("cannot reindex specific index(es) and system catalogs at the same time");
 			exit(1);
 		}
-
 		if (concurrentCons > 1)
 		{
 			pg_log_error("cannot use multiple jobs to reindex system catalogs");
 			exit(1);
 		}
+		if (outdated)
+		{
+			pg_log_error("cannot filter indexes having outdated dependencies "
+						 "and reindex system catalogs at the same time");
+			exit(1);
+		}
 
 		if (dbname == NULL)
 		{
@@ -274,7 +288,7 @@ main(int argc, char *argv[])
 
 		reindex_one_database(&cparams, REINDEX_SYSTEM, NULL,
 							 progname, echo, verbose,
-							 concurrently, 1, tablespace);
+							 concurrently, 1, tablespace, outdated);
 	}
 	else
 	{
@@ -304,17 +318,20 @@ main(int argc, char *argv[])
 		if (schemas.head != NULL)
 			reindex_one_database(&cparams, REINDEX_SCHEMA, &schemas,
 								 progname, echo, verbose,
-								 concurrently, concurrentCons, tablespace);
+								 concurrently, concurrentCons, tablespace,
+								 outdated);
 
 		if (indexes.head != NULL)
 			reindex_one_database(&cparams, REINDEX_INDEX, &indexes,
 								 progname, echo, verbose,
-								 concurrently, 1, tablespace);
+								 concurrently, 1, tablespace,
+								 outdated);
 
 		if (tables.head != NULL)
 			reindex_one_database(&cparams, REINDEX_TABLE, &tables,
 								 progname, echo, verbose,
-								 concurrently, concurrentCons, tablespace);
+								 concurrently, concurrentCons, tablespace,
+								 outdated);
 
 		/*
 		 * reindex database only if neither index nor table nor schema is
@@ -323,7 +340,8 @@ main(int argc, char *argv[])
 		if (indexes.head == NULL && tables.head == NULL && schemas.head == NULL)
 			reindex_one_database(&cparams, REINDEX_DATABASE, NULL,
 								 progname, echo, verbose,
-								 concurrently, concurrentCons, tablespace);
+								 concurrently, concurrentCons, tablespace,
+								 outdated);
 	}
 
 	exit(0);
@@ -334,7 +352,7 @@ reindex_one_database(ConnParams *cparams, ReindexType type,
 					 SimpleStringList *user_list,
 					 const char *progname, bool echo,
 					 bool verbose, bool concurrently, int concurrentCons,
-					 const char *tablespace)
+					 const char *tablespace, bool outdated)
 {
 	PGconn	   *conn;
 	SimpleStringListCell *cell;
@@ -363,6 +381,14 @@ reindex_one_database(ConnParams *cparams, ReindexType type,
 		exit(1);
 	}
 
+	if (outdated && PQserverVersion(conn) < 140000)
+	{
+		PQfinish(conn);
+		pg_log_error("cannot use the \"%s\" option on server versions older than PostgreSQL %s",
+					 "outdated", "14");
+		exit(1);
+	}
+
 	if (!parallel)
 	{
 		switch (process_type)
@@ -399,14 +425,24 @@ reindex_one_database(ConnParams *cparams, ReindexType type,
 				 */
 				if (concurrently)
 					pg_log_warning("cannot reindex system catalogs concurrently, skipping all");
+				else if (outdated)
+				{
+					/*
+					 * The only supported kind of object that can be outdated
+					 * is collation.  No system catalog has any index that can
+					 * depend on an outdated collation, so skip system
+					 * catalogs.
+					 */
+				}
 				else
 					run_reindex_command(conn, REINDEX_SYSTEM, PQdb(conn), echo,
 										verbose, concurrently, false,
-										tablespace);
+										tablespace, outdated);
 
 				/* Build a list of relations from the database */
 				process_list = get_parallel_object_list(conn, process_type,
-														user_list, echo);
+														user_list, outdated,
+														echo);
 				process_type = REINDEX_TABLE;
 
 				/* Bail out if nothing to process */
@@ -419,7 +455,8 @@ reindex_one_database(ConnParams *cparams, ReindexType type,
 
 				/* Build a list of relations from all the schemas */
 				process_list = get_parallel_object_list(conn, process_type,
-														user_list, echo);
+														user_list, outdated,
+														echo);
 				process_type = REINDEX_TABLE;
 
 				/* Bail out if nothing to process */
@@ -485,7 +522,8 @@ reindex_one_database(ConnParams *cparams, ReindexType type,
 
 		ParallelSlotSetHandler(free_slot, TableCommandResultHandler, NULL);
 		run_reindex_command(free_slot->connection, process_type, objname,
-							echo, verbose, concurrently, true, tablespace);
+							echo, verbose, concurrently, true, tablespace,
+							outdated);
 
 		cell = cell->next;
 	} while (cell != NULL);
@@ -510,7 +548,7 @@ finish:
 static void
 run_reindex_command(PGconn *conn, ReindexType type, const char *name,
 					bool echo, bool verbose, bool concurrently, bool async,
-					const char *tablespace)
+					const char *tablespace, bool outdated)
 {
 	const char *paren = "(";
 	const char *comma = ", ";
@@ -537,6 +575,12 @@ run_reindex_command(PGconn *conn, ReindexType type, const char *name,
 		sep = comma;
 	}
 
+	if (outdated)
+	{
+		appendPQExpBuffer(&sql, "%sOUTDATED", sep);
+		sep = comma;
+	}
+
 	if (sep != paren)
 		appendPQExpBufferStr(&sql, ") ");
 
@@ -642,7 +686,7 @@ run_reindex_command(PGconn *conn, ReindexType type, const char *name,
  */
 static SimpleStringList *
 get_parallel_object_list(PGconn *conn, ReindexType type,
-						 SimpleStringList *user_list, bool echo)
+						 SimpleStringList *user_list, bool outdated, bool echo)
 {
 	PQExpBufferData catalog_query;
 	PQExpBufferData buf;
@@ -661,16 +705,41 @@ get_parallel_object_list(PGconn *conn, ReindexType type,
 	{
 		case REINDEX_DATABASE:
 			Assert(user_list == NULL);
+
 			appendPQExpBufferStr(&catalog_query,
 								 "SELECT c.relname, ns.nspname\n"
 								 " FROM pg_catalog.pg_class c\n"
 								 " JOIN pg_catalog.pg_namespace ns"
-								 " ON c.relnamespace = ns.oid\n"
+								 " ON c.relnamespace = ns.oid\n");
+
+			if (outdated)
+			{
+				appendPQExpBufferStr(&catalog_query,
+									 " JOIN pg_catalog.pg_index i"
+									 " ON c.oid = i.indrelid\n"
+									 " JOIN pg_catalog.pg_class ci"
+									 " ON i.indexrelid = ci.oid\n");
+			}
+
+			appendPQExpBufferStr(&catalog_query,
 								 " WHERE ns.nspname != 'pg_catalog'\n"
 								 "   AND c.relkind IN ("
 								 CppAsString2(RELKIND_RELATION) ", "
-								 CppAsString2(RELKIND_MATVIEW) ")\n"
-								 " ORDER BY c.relpages DESC;");
+								 CppAsString2(RELKIND_MATVIEW) ")\n");
+
+			if (outdated)
+			{
+				appendPQExpBufferStr(&catalog_query,
+									 " GROUP BY c.relname, ns.nspname\n"
+									 " ORDER BY sum(ci.relpages)"
+									 " FILTER (WHERE pg_catalog.pg_index_has_outdated_dependency(ci.oid)) DESC;");
+			}
+			else
+			{
+				appendPQExpBufferStr(&catalog_query,
+									 " ORDER BY c.relpages DESC;");
+			}
+
 			break;
 
 		case REINDEX_SCHEMA:
@@ -688,7 +757,18 @@ get_parallel_object_list(PGconn *conn, ReindexType type,
 									 "SELECT c.relname, ns.nspname\n"
 									 " FROM pg_catalog.pg_class c\n"
 									 " JOIN pg_catalog.pg_namespace ns"
-									 " ON c.relnamespace = ns.oid\n"
+									 " ON c.relnamespace = ns.oid\n");
+
+				if (outdated)
+				{
+					appendPQExpBufferStr(&catalog_query,
+										 " JOIN pg_catalog.pg_index i"
+										 " ON c.oid = i.indrelid\n"
+										 " JOIN pg_catalog.pg_class ci"
+										 " ON i.indexrelid = ci.oid\n");
+				}
+
+				appendPQExpBufferStr(&catalog_query,
 									 " WHERE c.relkind IN ("
 									 CppAsString2(RELKIND_RELATION) ", "
 									 CppAsString2(RELKIND_MATVIEW) ")\n"
@@ -706,8 +786,20 @@ get_parallel_object_list(PGconn *conn, ReindexType type,
 					appendStringLiteralConn(&catalog_query, nspname, conn);
 				}
 
-				appendPQExpBufferStr(&catalog_query, ")\n"
-									 " ORDER BY c.relpages DESC;");
+				appendPQExpBufferStr(&catalog_query, ")\n");
+
+				if (outdated)
+				{
+					appendPQExpBufferStr(&catalog_query,
+										 " GROUP BY c.relname, ns.nspname\n"
+										 " ORDER BY sum(ci.relpages)"
+										 " FILTER (WHERE pg_catalog.pg_index_has_outdated_dependency(ci.oid)) DESC;");
+				}
+				else
+				{
+					appendPQExpBufferStr(&catalog_query,
+										 " ORDER BY c.relpages DESC;");
+				}
 			}
 			break;
 
@@ -755,7 +847,7 @@ static void
 reindex_all_databases(ConnParams *cparams,
 					  const char *progname, bool echo, bool quiet, bool verbose,
 					  bool concurrently, int concurrentCons,
-					  const char *tablespace)
+					  const char *tablespace, bool outdated)
 {
 	PGconn	   *conn;
 	PGresult   *result;
@@ -779,7 +871,7 @@ reindex_all_databases(ConnParams *cparams,
 
 		reindex_one_database(cparams, REINDEX_DATABASE, NULL,
 							 progname, echo, verbose, concurrently,
-							 concurrentCons, tablespace);
+							 concurrentCons, tablespace, outdated);
 	}
 
 	PQclear(result);
@@ -798,6 +890,7 @@ help(const char *progname)
 	printf(_("  -e, --echo                   show the commands being sent to the server\n"));
 	printf(_("  -i, --index=INDEX            recreate specific index(es) only\n"));
 	printf(_("  -j, --jobs=NUM               use this many concurrent connections to reindex\n"));
+	printf(_("      --outdated               only process indexes having outdated depencies\n"));
 	printf(_("  -q, --quiet                  don't write any messages\n"));
 	printf(_("  -s, --system                 reindex system catalogs\n"));
 	printf(_("  -S, --schema=SCHEMA          reindex specific schema(s) only\n"));
diff --git a/src/bin/scripts/t/090_reindexdb.pl b/src/bin/scripts/t/090_reindexdb.pl
index 159b637230..b60cac6081 100644
--- a/src/bin/scripts/t/090_reindexdb.pl
+++ b/src/bin/scripts/t/090_reindexdb.pl
@@ -3,7 +3,7 @@ use warnings;
 
 use PostgresNode;
 use TestLib;
-use Test::More tests => 58;
+use Test::More tests => 70;
 
 program_help_ok('reindexdb');
 program_version_ok('reindexdb');
@@ -174,6 +174,9 @@ $node->command_fails(
 $node->command_fails(
 	[ 'reindexdb', '-j', '2', '-i', 'i1', 'postgres' ],
 	'parallel reindexdb cannot process indexes');
+$node->command_fails(
+	[ 'reindexdb', '-s', '--outdated' ],
+	'cannot reindex system catalog and filter indexes having outdated dependencies');
 $node->issues_sql_like(
 	[ 'reindexdb', '-j', '2', 'postgres' ],
 	qr/statement:\ REINDEX SYSTEM postgres;
@@ -196,3 +199,32 @@ $node->command_checks_all(
 		qr/^reindexdb: warning: cannot reindex system catalogs concurrently, skipping all/s
 	],
 	'parallel reindexdb for system with --concurrently skips catalogs');
+
+# Temporarily downgrade client-min-message to get the no-op report
+$ENV{PGOPTIONS} = '--client-min-messages=NOTICE';
+$node->command_checks_all(
+	[ 'reindexdb',  '--outdated', '-v', '-t', 's1.t1', 'postgres' ],
+	0,
+	[qr/^$/],
+	[qr/table "t1" has no indexes to reindex/],
+	'verbose reindexdb for outdated dependencies on a specific table reports no-op tables');
+
+$node->command_checks_all(
+	[ 'reindexdb',  '--outdated', '-v', '-d', 'postgres' ],
+	0,
+	[qr/^$/],
+	[qr/^$/],
+	'verbose reindexdb for outdated dependencies database wide silently ignore all tables');
+$node->command_checks_all(
+	[ 'reindexdb',  '--outdated', '-v', '-j', '2', '-d', 'postgres' ],
+	0,
+	[qr/^$/],
+	[qr/table "t1" has no indexes to reindex/],
+	'parallel verbose reindexdb for outdated dependencies database wide reports no-op tables');
+
+# Switch back to WARNING client-min-message
+$ENV{PGOPTIONS} = '--client-min-messages=WARNING';
+$node->issues_sql_like(
+	[ 'reindexdb', '--outdated', '-t', 's1.t1', 'postgres' ],
+	qr/.*statement: REINDEX \(OUTDATED\) TABLE s1\.t1;/,
+	'reindexdb for outdated dependencies specify the OUTDATED keyword');
-- 
2.30.1

