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MySQL数据库update更新子查询

时间:2021-07-01 10:21:17 帮助过:5人阅读

比如:

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1 2 3 4 UPDATE test.tb_vobile a set a.name = ‘111 ‘ WHERE a.id = (select max(id) id from test.tb_vobile)

报错:

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1 2 3 4 5 6 7 [SQL]UPDATE test.tb_vobile a set a.name = ‘111 ‘ WHERE a.id = (select max(id) id from test.tb_vobile)  

以下可通过:

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1 2 3 4 5 6 7 8 9 10 11 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;

1 2 3 4 UPDATE test.tb_vobile a set a.name = ‘111 ‘ WHERE a.id = (select max(id) id from test.tb_vobile)

报错:

?
1 2 3 4 5 6 7 [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:

?
1 2 3 4 5 6 7 8 9 10 11 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;

MySQL数据库update更新子查询

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