Stop background daemon before dropping the database (#6688)

DESCRIPTION: Stop maintenance daemon when dropping a database even
without Citus extension

Fixes #6670

src/backend/distributed/commands/utility_hook.c

@@ -219,6 +219,23 @@ multi_ProcessUtility(PlannedStmt *pstmt,
 		PreprocessCreateExtensionStmtForCitusColumnar(parsetree);
 	}
 
+	/*
+	 * Make sure that on DROP DATABASE we terminate the background daemon
+	 * associated with it.
+	 */
+	if (IsA(parsetree, DropdbStmt))
+	{
+		const bool missingOK = true;
+		DropdbStmt *dropDbStatement = (DropdbStmt *) parsetree;
+		char *dbname = dropDbStatement->dbname;
+		Oid databaseOid = get_database_oid(dbname, missingOK);
+
+		if (OidIsValid(databaseOid))
+		{
+			StopMaintenanceDaemon(databaseOid);
+		}
+	}
+
 	if (!CitusHasBeenLoaded())
 	{
 		/*
@@ -678,22 +695,9 @@ ProcessUtilityInternal(PlannedStmt *pstmt,
 	}
 
 	/*
-	 * Make sure that on DROP DATABASE we terminate the background daemon
+	 * Make sure that on DROP EXTENSION we terminate the background daemon
 	 * associated with it.
 	 */
-	if (IsA(parsetree, DropdbStmt))
-	{
-		const bool missingOK = true;
-		DropdbStmt *dropDbStatement = (DropdbStmt *) parsetree;
-		char *dbname = dropDbStatement->dbname;
-		Oid databaseOid = get_database_oid(dbname, missingOK);
-
-		if (OidIsValid(databaseOid))
-		{
-			StopMaintenanceDaemon(databaseOid);
-		}
-	}
-
 	if (IsDropCitusExtensionStmt(parsetree))
 	{
 		StopMaintenanceDaemon(MyDatabaseId);

src/test/regress/expected/drop_database.out

@@ -0,0 +1,43 @@
+-- coordinator
+CREATE SCHEMA drop_database;
+SET search_path TO drop_database;
+SET citus.shard_count TO 4;
+SET citus.shard_replication_factor TO 1;
+SET citus.next_shard_id TO 35137400;
+CREATE DATABASE citus_created;
+NOTICE:  Citus partially supports CREATE DATABASE for distributed databases
+DETAIL:  Citus does not propagate CREATE DATABASE command to workers
+HINT:  You can manually create a database and its extensions on workers.
+\c citus_created
+CREATE EXTENSION citus;
+CREATE DATABASE citus_not_created;
+NOTICE:  Citus partially supports CREATE DATABASE for distributed databases
+DETAIL:  Citus does not propagate CREATE DATABASE command to workers
+HINT:  You can manually create a database and its extensions on workers.
+\c citus_not_created
+DROP DATABASE citus_created;
+\c regression
+DROP DATABASE citus_not_created;
+-- worker1
+\c - - - :worker_1_port
+SET search_path TO drop_database;
+SET citus.shard_count TO 4;
+SET citus.shard_replication_factor TO 1;
+SET citus.next_shard_id TO 35137400;
+CREATE DATABASE citus_created;
+NOTICE:  Citus partially supports CREATE DATABASE for distributed databases
+DETAIL:  Citus does not propagate CREATE DATABASE command to workers
+HINT:  You can manually create a database and its extensions on workers.
+\c citus_created
+CREATE EXTENSION citus;
+CREATE DATABASE citus_not_created;
+NOTICE:  Citus partially supports CREATE DATABASE for distributed databases
+DETAIL:  Citus does not propagate CREATE DATABASE command to workers
+HINT:  You can manually create a database and its extensions on workers.
+\c citus_not_created
+DROP DATABASE citus_created;
+\c regression
+DROP DATABASE citus_not_created;
+\c - - - :master_port
+SET client_min_messages TO WARNING;
+DROP SCHEMA drop_database CASCADE;

src/test/regress/multi_schedule

@@ -121,3 +121,4 @@ test: ensure_no_shared_connection_leak
 test: check_mx
 
 test: generated_identity
+test: drop_database

src/test/regress/sql/drop_database.sql

@@ -0,0 +1,45 @@
+-- coordinator
+CREATE SCHEMA drop_database;
+SET search_path TO drop_database;
+SET citus.shard_count TO 4;
+SET citus.shard_replication_factor TO 1;
+SET citus.next_shard_id TO 35137400;
+
+CREATE DATABASE citus_created;
+
+\c citus_created
+CREATE EXTENSION citus;
+
+CREATE DATABASE citus_not_created;
+
+\c citus_not_created
+DROP DATABASE citus_created;
+
+\c regression
+DROP DATABASE citus_not_created;
+
+-- worker1
+\c - - - :worker_1_port
+
+SET search_path TO drop_database;
+SET citus.shard_count TO 4;
+SET citus.shard_replication_factor TO 1;
+SET citus.next_shard_id TO 35137400;
+
+CREATE DATABASE citus_created;
+
+\c citus_created
+CREATE EXTENSION citus;
+
+CREATE DATABASE citus_not_created;
+
+\c citus_not_created
+DROP DATABASE citus_created;
+
+\c regression
+DROP DATABASE citus_not_created;
+
+\c - - - :master_port
+
+SET client_min_messages TO WARNING;
+DROP SCHEMA drop_database CASCADE;