求解答
select * from b
Having Count(*)>1
https://blog.csdn.net/weixin_43167662/article/details/127734546
SQL Server 一列或多列重复数据的查询，删除 - 无忧岛主 - 博客园 (cnblogs.com)
参考
sql语句查询重复的数据 - 代码改变世界&1024 - 博客园 (cnblogs.com)
select t1.aa,(select count(*) from table1 t2 where t2.aa=t1.aa) from table1 t1
-- 开窗函数
select sid,student_id,count(sid) over(PARTITION by student_id order
by student_id) 及格数 from score where num>= 60;
1min目标场景问卷
立即参与
