You can’t specify target table tbl for update in FROM clause
在mysql中当在一句sql中先后执行对同一张表的select 和 update 或 delete 操作时,就会报错: You can't specify target table tbl for update in FROM clause
例如:
update tbl as a set a.col =
(
select b.col from tbl as b where b.id = 1
);
解决方法: 将select字句中的表再嵌套一层select
update tbl as a set a.col =
(
select c.col from
(
select * from tbl as b where b.id = 1
)
as c
);