Error Code: 1093. You can't specify target table,delete或者update的where条件中有子查询解决办法

Error Code: 1093. You can't specify target table 'ws_product' for update in FROM clause

这个是我们在使用update或者delete语句时,在where条件里面加入的子查询导致的。例如如下的update语句:

update table set type = 'static' where id in (
select id from ws_product where first_name ='superman'
);


修改上述语句为下面这样,该问题可以解决:

update ws_product set type = 'static' where id in (
select id form (
 select id from ws_product where first_name ='superman'
) xx
);

注意,这样一定要给最里面的子查询定义一个别名,不然会报另外一个错误:



自己的例子:
Error Code: 1093. You can't specify target table,delete或者update的where条件中有子查询解决办法_第1张图片
下面这种方式报错   error code:1093
DELETE FROM Persons WHERE id NOT IN (SELECT MAX(id) FROM Persons GROUP BY NAME,age)

所以改成:
DELETE FROM Persons WHERE id NOT IN (SELECT * FROM (SELECT MAX(id) FROM Persons GROUP BY NAME,age) temp);
原因:一定要给最里面的子查询定义一个别名,

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