MySQL数据库update更新子查询

比如:

UPDATE test.tb_vobile a 
set a.name = '111 '
WHERE
a.id = (select max(id) id from test.tb_vobile) 

报错:

[SQL]UPDATE test.tb_vobile a 
set a.name = '111 '
WHERE
a.id = (select max(id) id from test.tb_vobile) 


[Err] 1093 - You can't specify target table 'a' for update in FROM clause


以下可通过:

UPDATE test.tb_vobile a 
join 
(select max(id) id from test.tb_vobile) b 
on a.id = b.id 
set a.name = '123 ';

UPDATE test.tb_vobile a ,(select max(id) id from test.tb_vobile) b 
set a.name = '321 '
WHERE
a.id = b.id ;

说明:

1、update 时,更新的表不能在set和where中用于子查询;
2、update 时,可以对多个表进行更新(sqlserver不行);
如:update ta a,tb b set a.Bid=b.id ,b.Aid=a.id;  
3、update 后面可以做任意的查询,这个作用等同于from;

posted on 2015-04-24 18:00  吴一达  阅读(1194)  评论(0编辑  收藏  举报

导航