From 70d300969fbd2aae6c66b36f6100d3d2516a0dab Mon Sep 17 00:00:00 2001
From: Kyotaro Horiguchi <horikyoga.ntt@gmail.com>
Date: Wed, 11 Nov 2020 23:21:09 +0900
Subject: [PATCH v4 2/2] New command ALTER TABLE ALL IN TABLESPACE SET
 LOGGED/UNLOGGED

To ease invoking ALTER TABLE SET LOGGED/UNLOGGED, this command changes
relation persistence of all tables in the specified tablespace.
---
 src/backend/commands/tablecmds.c | 140 +++++++++++++++++++++++++++++++
 src/backend/nodes/copyfuncs.c    |  16 ++++
 src/backend/nodes/equalfuncs.c   |  15 ++++
 src/backend/parser/gram.y        |  20 +++++
 src/backend/tcop/utility.c       |  11 +++
 src/include/commands/tablecmds.h |   2 +
 src/include/nodes/nodes.h        |   1 +
 src/include/nodes/parsenodes.h   |   9 ++
 8 files changed, 214 insertions(+)

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 37a15d31ee..2f65abb19b 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -13696,6 +13696,146 @@ AlterTableMoveAll(AlterTableMoveAllStmt *stmt)
 	return new_tablespaceoid;
 }
 
+/*
+ * Alter Table ALL ... SET LOGGED/UNLOGGED
+ *
+ * Allows a user to change persistence of all objects in a given tablespace in
+ * the current database.  Objects can be chosen based on the owner of the
+ * object also, to allow users to change persistene only their objects. The
+ * main permissions handling is done by the lower-level change persistence
+ * function.
+ *
+ * All to-be-modified objects are locked first. If NOWAIT is specified and the
+ * lock can't be acquired then we ereport(ERROR).
+ */
+void
+AlterTableSetLoggedAll(AlterTableSetLoggedAllStmt *stmt)
+{
+	List	   *relations = NIL;
+	ListCell   *l;
+	ScanKeyData key[1];
+	Relation	rel;
+	TableScanDesc scan;
+	HeapTuple	tuple;
+	Oid			tablespaceoid;
+	List	   *role_oids = roleSpecsToIds(NIL);
+
+	/* Ensure we were not asked to change something we can't */
+	if (stmt->objtype != OBJECT_TABLE)
+		ereport(ERROR,
+				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
+				 errmsg("only tables can be specified")));
+
+	/* Get the tablespace OID */
+	tablespaceoid = get_tablespace_oid(stmt->tablespacename, false);
+
+	/*
+	 * Now that the checks are done, check if we should set either to
+	 * InvalidOid because it is our database's default tablespace.
+	 */
+	if (tablespaceoid == MyDatabaseTableSpace)
+		tablespaceoid = InvalidOid;
+
+	/*
+	 * Walk the list of objects in the tablespace to pick up them. This will
+	 * only find objects in our database, of course.
+	 */
+	ScanKeyInit(&key[0],
+				Anum_pg_class_reltablespace,
+				BTEqualStrategyNumber, F_OIDEQ,
+				ObjectIdGetDatum(tablespaceoid));
+
+	rel = table_open(RelationRelationId, AccessShareLock);
+	scan = table_beginscan_catalog(rel, 1, key);
+	while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
+	{
+		Form_pg_class relForm = (Form_pg_class) GETSTRUCT(tuple);
+		Oid			relOid = relForm->oid;
+
+		/*
+		 * Do not pick-up objects in pg_catalog as part of this, if an admin
+		 * really wishes to do so, they can issue the individual ALTER
+		 * commands directly.
+		 *
+		 * Also, explicitly avoid any shared tables, temp tables, or TOAST
+		 * (TOAST will be changed with the main table).
+		 */
+		if (IsCatalogNamespace(relForm->relnamespace) ||
+			relForm->relisshared ||
+			isAnyTempNamespace(relForm->relnamespace) ||
+			IsToastNamespace(relForm->relnamespace))
+			continue;
+
+		/* Only pick up the object type requested */
+		if (relForm->relkind != RELKIND_RELATION)
+			continue;
+
+		/* Check if we are only picking-up objects owned by certain roles */
+		if (role_oids != NIL && !list_member_oid(role_oids, relForm->relowner))
+			continue;
+
+		/*
+		 * Handle permissions-checking here since we are locking the tables
+		 * and also to avoid doing a bunch of work only to fail part-way. Note
+		 * that permissions will also be checked by AlterTableInternal().
+		 *
+		 * Caller must be considered an owner on the table of which we're going
+		 * to change persistence.
+		 */
+		if (!pg_class_ownercheck(relOid, GetUserId()))
+			aclcheck_error(ACLCHECK_NOT_OWNER, get_relkind_objtype(get_rel_relkind(relOid)),
+						   NameStr(relForm->relname));
+
+		if (stmt->nowait &&
+			!ConditionalLockRelationOid(relOid, AccessExclusiveLock))
+			ereport(ERROR,
+					(errcode(ERRCODE_OBJECT_IN_USE),
+					 errmsg("aborting because lock on relation \"%s.%s\" is not available",
+							get_namespace_name(relForm->relnamespace),
+							NameStr(relForm->relname))));
+		else
+			LockRelationOid(relOid, AccessExclusiveLock);
+
+		/*
+		 * Add to our list of objects of which we're going to change
+		 * persistence.
+		 */
+		relations = lappend_oid(relations, relOid);
+	}
+
+	table_endscan(scan);
+	table_close(rel, AccessShareLock);
+
+	if (relations == NIL)
+		ereport(NOTICE,
+				(errcode(ERRCODE_NO_DATA_FOUND),
+				 errmsg("no matching relations in tablespace \"%s\" found",
+						tablespaceoid == InvalidOid ? "(database default)" :
+						get_tablespace_name(tablespaceoid))));
+
+	/*
+	 * Everything is locked, loop through and change persistence of all of the
+	 * relations.
+	 */
+	foreach(l, relations)
+	{
+		List	   *cmds = NIL;
+		AlterTableCmd *cmd = makeNode(AlterTableCmd);
+
+		if (stmt->logged)
+			cmd->subtype = AT_SetLogged;
+		else
+			cmd->subtype = AT_SetUnLogged;
+
+		cmds = lappend(cmds, cmd);
+
+		EventTriggerAlterTableStart((Node *) stmt);
+		/* OID is set by AlterTableInternal */
+		AlterTableInternal(lfirst_oid(l), cmds, false);
+		EventTriggerAlterTableEnd();
+	}
+}
+
 static void
 index_copy_data(Relation rel, RelFileNode newrnode)
 {
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index ba3ccc712c..127da5151d 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -4138,6 +4138,19 @@ _copyAlterTableMoveAllStmt(const AlterTableMoveAllStmt *from)
 	return newnode;
 }
 
+static AlterTableSetLoggedAllStmt *
+_copyAlterTableSetLoggedAllStmt(const AlterTableSetLoggedAllStmt *from)
+{
+	AlterTableSetLoggedAllStmt *newnode = makeNode(AlterTableSetLoggedAllStmt);
+
+	COPY_STRING_FIELD(tablespacename);
+	COPY_SCALAR_FIELD(objtype);
+	COPY_SCALAR_FIELD(logged);
+	COPY_SCALAR_FIELD(nowait);
+
+	return newnode;
+}
+
 static CreateExtensionStmt *
 _copyCreateExtensionStmt(const CreateExtensionStmt *from)
 {
@@ -5441,6 +5454,9 @@ copyObjectImpl(const void *from)
 		case T_AlterTableMoveAllStmt:
 			retval = _copyAlterTableMoveAllStmt(from);
 			break;
+		case T_AlterTableSetLoggedAllStmt:
+			retval = _copyAlterTableSetLoggedAllStmt(from);
+			break;
 		case T_CreateExtensionStmt:
 			retval = _copyCreateExtensionStmt(from);
 			break;
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index a2ef853dc2..4f13a1762b 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -1872,6 +1872,18 @@ _equalAlterTableMoveAllStmt(const AlterTableMoveAllStmt *a,
 	return true;
 }
 
+static bool
+_equalAlterTableSetLoggedAllStmt(const AlterTableSetLoggedAllStmt *a,
+								 const AlterTableSetLoggedAllStmt *b)
+{
+	COMPARE_STRING_FIELD(tablespacename);
+	COMPARE_SCALAR_FIELD(objtype);
+	COMPARE_SCALAR_FIELD(logged);
+	COMPARE_SCALAR_FIELD(nowait);
+
+	return true;
+}
+
 static bool
 _equalCreateExtensionStmt(const CreateExtensionStmt *a, const CreateExtensionStmt *b)
 {
@@ -3494,6 +3506,9 @@ equal(const void *a, const void *b)
 		case T_AlterTableMoveAllStmt:
 			retval = _equalAlterTableMoveAllStmt(a, b);
 			break;
+		case T_AlterTableSetLoggedAllStmt:
+			retval = _equalAlterTableSetLoggedAllStmt(a, b);
+			break;
 		case T_CreateExtensionStmt:
 			retval = _equalCreateExtensionStmt(a, b);
 			break;
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 31c95443a5..2222fd8fe3 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -1934,6 +1934,26 @@ AlterTableStmt:
 					n->nowait = $13;
 					$$ = (Node *)n;
 				}
+		|	ALTER TABLE ALL IN_P TABLESPACE name SET LOGGED opt_nowait
+				{
+					AlterTableSetLoggedAllStmt *n =
+						makeNode(AlterTableSetLoggedAllStmt);
+					n->tablespacename = $6;
+					n->objtype = OBJECT_TABLE;
+					n->logged = true;
+					n->nowait = $9;
+					$$ = (Node *)n;
+				}
+		|	ALTER TABLE ALL IN_P TABLESPACE name SET UNLOGGED opt_nowait
+				{
+					AlterTableSetLoggedAllStmt *n =
+						makeNode(AlterTableSetLoggedAllStmt);
+					n->tablespacename = $6;
+					n->objtype = OBJECT_TABLE;
+					n->logged = false;
+					n->nowait = $9;
+					$$ = (Node *)n;
+				}
 		|	ALTER INDEX qualified_name alter_table_cmds
 				{
 					AlterTableStmt *n = makeNode(AlterTableStmt);
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 53a511f1da..16606448bf 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -161,6 +161,7 @@ ClassifyUtilityCommandAsReadOnly(Node *parsetree)
 		case T_AlterTSConfigurationStmt:
 		case T_AlterTSDictionaryStmt:
 		case T_AlterTableMoveAllStmt:
+		case T_AlterTableSetLoggedAllStmt:
 		case T_AlterTableSpaceOptionsStmt:
 		case T_AlterTableStmt:
 		case T_AlterTypeStmt:
@@ -1732,6 +1733,12 @@ ProcessUtilitySlow(ParseState *pstate,
 				commandCollected = true;
 				break;
 
+			case T_AlterTableSetLoggedAllStmt:
+				AlterTableSetLoggedAll((AlterTableSetLoggedAllStmt *) parsetree);
+				/* commands are stashed in AlterTableSetLoggedAll */
+				commandCollected = true;
+				break;
+
 			case T_DropStmt:
 				ExecDropStmt((DropStmt *) parsetree, isTopLevel);
 				/* no commands stashed for DROP */
@@ -2619,6 +2626,10 @@ CreateCommandTag(Node *parsetree)
 			tag = AlterObjectTypeCommandTag(((AlterTableMoveAllStmt *) parsetree)->objtype);
 			break;
 
+		case T_AlterTableSetLoggedAllStmt:
+			tag = AlterObjectTypeCommandTag(((AlterTableSetLoggedAllStmt *) parsetree)->objtype);
+			break;
+
 		case T_AlterTableStmt:
 			tag = AlterObjectTypeCommandTag(((AlterTableStmt *) parsetree)->objtype);
 			break;
diff --git a/src/include/commands/tablecmds.h b/src/include/commands/tablecmds.h
index 08c463d3c4..646928466d 100644
--- a/src/include/commands/tablecmds.h
+++ b/src/include/commands/tablecmds.h
@@ -42,6 +42,8 @@ extern void AlterTableInternal(Oid relid, List *cmds, bool recurse);
 
 extern Oid	AlterTableMoveAll(AlterTableMoveAllStmt *stmt);
 
+extern void AlterTableSetLoggedAll(AlterTableSetLoggedAllStmt *stmt);
+
 extern ObjectAddress AlterTableNamespace(AlterObjectSchemaStmt *stmt,
 										 Oid *oldschema);
 
diff --git a/src/include/nodes/nodes.h b/src/include/nodes/nodes.h
index caed683ba9..16d91d3e1d 100644
--- a/src/include/nodes/nodes.h
+++ b/src/include/nodes/nodes.h
@@ -424,6 +424,7 @@ typedef enum NodeTag
 	T_AlterCollationStmt,
 	T_CallStmt,
 	T_AlterStatsStmt,
+	T_AlterTableSetLoggedAllStmt,
 
 	/*
 	 * TAGS FOR PARSE TREE NODES (parsenodes.h)
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index dc2bb40926..c3eab6f1ab 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2253,6 +2253,15 @@ typedef struct AlterTableMoveAllStmt
 	bool		nowait;
 } AlterTableMoveAllStmt;
 
+typedef struct AlterTableSetLoggedAllStmt
+{
+	NodeTag		type;
+	char	   *tablespacename;
+	ObjectType	objtype;		/* Object type to move */
+	bool		logged;
+	bool		nowait;
+} AlterTableSetLoggedAllStmt;
+
 /* ----------------------
  *		Create/Alter Extension Statements
  * ----------------------
-- 
2.27.0

