BEGIN; CREATE FUNCTION f () RETURNS boolean AS ' DECLARE i RECORD; BEGIN FOR i IN SELECT relname FROM pg_class WHERE relkind = \'r\' AND relname LIKE \'_%_data\' LOOP EXECUTE \'UPDATE \' || i.relname || \' SET _start_t=\\\'1970/1/1 00:00:00 UTC\\\' WHERE _start_t IS NULL\'; END LOOP; RETURN true; END; ' LANGUAGE 'plpgsql'; SELECT f(); DROP FUNCTION f(); COMMIT;