Support CREATE SCHEMA without name (#5782)

src/backend/distributed/commands/schema.c

@@ -223,7 +223,24 @@ CreateSchemaStmtObjectAddress(Node *node, bool missing_ok)
 {
 	CreateSchemaStmt *stmt = castNode(CreateSchemaStmt, node);
 
-	return GetObjectAddressBySchemaName(stmt->schemaname, missing_ok);
+	StringInfoData schemaName = { 0 };
+	initStringInfo(&schemaName);
+
+	if (stmt->schemaname == NULL)
+	{
+		/*
+		 * If the schema name is not provided, the schema will be created
+		 * with the name of the authorizated user.
+		 */
+		Assert(stmt->authrole != NULL);
+		appendStringInfoString(&schemaName, RoleSpecString(stmt->authrole, true));
+	}
+	else
+	{
+		appendStringInfoString(&schemaName, stmt->schemaname);
+	}
+
+	return GetObjectAddressBySchemaName(schemaName.data, missing_ok);
 }
 
 

src/backend/distributed/deparser/deparse_schema_stmts.c

@@ -92,11 +92,6 @@ AppendCreateSchemaStmt(StringInfo buf, CreateSchemaStmt *stmt)
 		elog(ERROR, "schema creating is not supported with other create commands");
 	}
 
-	if (stmt->schemaname == NULL)
-	{
-		elog(ERROR, "schema name should be specified");
-	}
-
 	appendStringInfoString(buf, "CREATE SCHEMA ");
 
 	if (stmt->if_not_exists)
@@ -104,7 +99,19 @@ AppendCreateSchemaStmt(StringInfo buf, CreateSchemaStmt *stmt)
 		appendStringInfoString(buf, "IF NOT EXISTS ");
 	}
 
-	appendStringInfo(buf, "%s ", quote_identifier(stmt->schemaname));
+	if (stmt->schemaname != NULL)
+	{
+		appendStringInfo(buf, "%s ", quote_identifier(stmt->schemaname));
+	}
+	else
+	{
+		/*
+		 * If the schema name is not provided, the schema will be created
+		 * with the name of the authorizated user.
+		 */
+		Assert(stmt->authrole != NULL);
+		appendStringInfo(buf, "%s ", RoleSpecString(stmt->authrole, true));
+	}
 
 	if (stmt->authrole != NULL)
 	{

src/test/regress/expected/multi_mx_schema_support.out

@@ -538,7 +538,28 @@ SELECT run_command_on_workers($$DROP SCHEMA localschema;$$);
  (localhost,57638,f,"ERROR:  schema ""localschema"" does not exist")
 (2 rows)
 
+CREATE ROLE schema_owner WITH LOGIN;
+NOTICE:  not propagating CREATE ROLE/USER commands to worker nodes
+HINT:  Connect to worker nodes directly to manually create all necessary users and roles.
+SELECT run_command_on_workers($$CREATE ROLE schema_owner WITH LOGIN;$$);
+      run_command_on_workers
+---------------------------------------------------------------------
+ (localhost,57637,t,"CREATE ROLE")
+ (localhost,57638,t,"CREATE ROLE")
+(2 rows)
+
 RESET citus.enable_ddl_propagation;
+-- create schema with the name of the owner
+CREATE SCHEMA AUTHORIZATION schema_owner;
+-- verify the schema is created on workers
+SELECT run_command_on_workers($$SELECT COUNT(*) FROM pg_namespace WHERE nspname='schema_owner';$$);
+ run_command_on_workers
+---------------------------------------------------------------------
+ (localhost,57637,t,1)
+ (localhost,57638,t,1)
+(2 rows)
+
+DROP SCHEMA schema_owner;
 DROP SCHEMA mx_old_schema CASCADE;
 DROP SCHEMA mx_new_schema CASCADE;
 NOTICE:  drop cascades to table mx_new_schema.table_set_schema

src/test/regress/sql/multi_mx_schema_support.sql

@@ -351,7 +351,15 @@ CREATE SCHEMA localschema;
 -- should error out
 SELECT run_command_on_workers($$DROP SCHEMA localschema;$$);
 
+CREATE ROLE schema_owner WITH LOGIN;
+SELECT run_command_on_workers($$CREATE ROLE schema_owner WITH LOGIN;$$);
 RESET citus.enable_ddl_propagation;
+-- create schema with the name of the owner
+CREATE SCHEMA AUTHORIZATION schema_owner;
+-- verify the schema is created on workers
+SELECT run_command_on_workers($$SELECT COUNT(*) FROM pg_namespace WHERE nspname='schema_owner';$$);
+
+DROP SCHEMA schema_owner;
 
 DROP SCHEMA mx_old_schema CASCADE;
 DROP SCHEMA mx_new_schema CASCADE;