sql删除重复记录 You can't specify target table '表名' for update in FROM clause

用下面的语句就报语法出错：

delete from 表名 where 字段名 not in 
(select min(c.字段名) as 字段名 from 表名 c group by (c.字段名));

报错如下：You can't specify target table '表名' for update in FROM clause

找到替代方案，改用下面的，OK:

delete from 表名 where 字段名 not in 
(select min(c.字段名) as 字段名 from (select * from 表名) c group by (c.字段名));

或者下面的也OK：

delete from 表名 where 字段名 not in 
(select * from (select min(字段名) as 字段名 from 表名 group by (字段名)) v);