如果不加黑体部分会报1093错误,
原因:Mysql在执行修改或删除的时候,子查询不能是同一张表
1、第一种方式:
DELETE FROM users WHERE user_id NOT IN
(SELECT temp.user_id FROM
(SELECT MAX(user_id) user_id FROM users GROUP BY name, age
having COUNT(*) >= 1)
temp)
2、第二种方式:
循环执行如下语句
DELETE users FROM users , (SELECT user_id FROM users
GROUP BY name, age
having COUNT(*) > 1) AS t1
WHERE users .user_id = t1.qzkh_id