20 lines
506 B
PL/PgSQL
20 lines
506 B
PL/PgSQL
BEGIN;
|
|
|
|
-- 在同一事务取得排他锁后检查并删除，避免检查与删表之间写入新通知事实。
|
|
DO $$
|
|
BEGIN
|
|
IF to_regclass('tb_notification') IS NULL THEN
|
|
RETURN;
|
|
END IF;
|
|
|
|
LOCK TABLE tb_notification IN ACCESS EXCLUSIVE MODE;
|
|
IF EXISTS (SELECT 1 FROM tb_notification LIMIT 1) THEN
|
|
RAISE EXCEPTION 'tb_notification 已存在通知事实，禁止删表回滚，请停止生产者后向前修复';
|
|
END IF;
|
|
|
|
DROP TABLE tb_notification;
|
|
END
|
|
$$;
|
|
|
|
COMMIT;
|