首先你要知道你说的重复是根据什么而做出的判断。其次,你的SQL语句显然不对:select user_classnumber from 07record.record_admin having GROUP BY user_classnum,having子句一定在最后面的,而且在select中一定要有统计字段才行。
SELECT DISTINCT field FROM table
根据其中的一个字段 比如座号 姓名001 A 001 B 002 C座号001 就是重复的记录 我想把座号重复的找出来
select count(*),seatnumber as c from aaa group by seatnumber having c>1;如果这个不行, select count(*),seatnumber as c from aaa group by seatnumber having count(*)>1;
上面的代码有点问题,select count(*) as c,seatnumber from aaa group by seatnumber having c>1; 或者 select count(*),seatnumber from aaa group by seatnumber having count(*)>1
select * from 07record.record_admin where user_classnumber in( select user_classnumber from 07record.record_admin GROUP BY user_classnum having count(*) >1) 按你的意思,这样写看看,不过效率太慢。select * from 07record.record_admin a where (SELECT COUNT(1) FROM 07record.record_admin WHERE a.user_classnumber=user_classnumber)>)
001 B
002 C座号001 就是重复的记录 我想把座号重复的找出来
select count(*),seatnumber as c from aaa group by seatnumber having c>1;如果这个不行,
select count(*),seatnumber as c from aaa group by seatnumber having count(*)>1;
select user_classnumber from 07record.record_admin GROUP BY user_classnum having count(*) >1)
按你的意思,这样写看看,不过效率太慢。select * from 07record.record_admin a where (SELECT COUNT(1) FROM 07record.record_admin WHERE a.user_classnumber=user_classnumber)>)