MySQL 常用T-SQL(持续更新...)

1、判断表中如果没有则插入新纪录

INSERT INTO table(field1, field2, fieldn) 
SELECT 'field1', 'field2', 'fieldn' 
FROM DUAL
WHERE NOT EXISTS(SELECT field FROM table WHERE field = ?)

 

posted @ 2021-11-29 13:45  war3_xiaofeng  阅读(125)  评论(0编辑  收藏  举报