刪除Mysql重複數據

delete from t_user where userId in(
select userId from t_user GROUP BY userId having count(*)>1)
and id not in(select min(id)as id from t_user group by userId having count(*)>1) and status=0;

刪除重複數據時，可能會出現You can't specify target table for update in FROM clause錯誤的意思是說，不能先select出同一表中的某些值，再update這個表(在同一語句中)，組要在select重查一遍以免該錯誤。

delete from t_user where userId in(
select t.userId from 
(select userId from t_user GROUP BY userId having count(*)>1)t)
and id not in(select tb.id from 
(select min(id)as id from t_user group by userId having count(*)>1)tb) and status=0;