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一张数据表,存在重复数据.sElECt ID,NAmE,COUNT(...

select ID, count(Name) from A group by ID having count(Name) > 1

select ID,count(ID) from tablename group by ID having (count(ID)>1)

select name,count(1)from tabnamegroup by namehaving count(1) > 1

1、查出表中重复列的数据:select a,count(*) from table group by a having count(*)>1 2、查重复次数最多的列:select a,num from (select a,count(*) num from table group by a having count(*)>1)order by num desc 此外,还有 1、查询一个...

--查询指定条件下的重复次数--测试数据with tabname(id,name) as (select 1,'name1' union allselect 1,'name1' union allselect 1,'name1' union allselect 1,'name2' union allselect 1,'name2' union allselect 1,'name3' union allselect 2,...

select testid,count(1) from testtable group by testid having count(1)>1 count(1)就是重复在数量 如何查询重复的数据 select 字段1,字段2,count(*) from 表名 group by 字段1,字段2 having count(*) > 1 PS:将上面的>号改为=号就可以查询出...

/*难道是下面的这种? select * from LinkUser where Lname=UserName; */ 意思是去除重复的? select * from LinkUser a where exists (select 1 from (select min(id),Lname from LinkUser group by Lname) b where a.id=b.id)

1、必须保证表中有主键或者唯一索引,或者某列数据不能重复。只有这样,才可能使用一句SQL来实现。否则只能考虑其它办法。下面的语句,假定BB列是不重复的,删除后保存BB列值最大的那条记录。 delete from 表 where aa in (select aa from 表 gr...

DELETE FROM EMP E WHERE E.id> (SELECT MIN(X.id) FROM EMP X WHERE X.EMP_NO = E.EMP_NO and ...);语句中and后面是所有出标志列id的字段全部相同,那么则删除比最小ID大的所有相同记录。因为最小的就一条记录,所以结果就只剩一条记录了。

你是要查找数据库中某个字段下的相同数据吧,我给你写2个例子 (数据库执行效率高) select * from dbo.MediafileInfo as a where (VideoDownUrl IN (SELECT VideoDownUrl FROM MediafileInfo AS B WHERE A.ProgramID B.ProgramID)) (数据库执行效...

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