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[数据库]MySQL数据库update更新子查询


比如:

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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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[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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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
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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;