请教各位!, 简单问题, 在线

[dddd8888]

例:
table a
field1, field2, field3

field1, 和 field2 组合起来可能有重复
我想把有重复的记录都取出来, 无重复的剔除在外,
该怎样写 SQL 语句?

[txlicenhe]

select field1,field2 from tableA
group by field1,field2
having count(*) > 1

[dddd8888]

谢谢,
但我还想把field3也显示出来

[txlicenhe]

select a.* from tableA a
join (
select field1,field2 from tableA
group by field1,field2
having count(*) > 1) b on a.field1 = b.field1 and a.field2 = b.field2

[gmlxf]

select field1,field2 from a
group by field1,field2
having count(*) > 1

-- 如果想列出所有字段，你用下面的：
select * from tableA a
where (select count(*) from tableA where field1=a.field1 and field2=a.field2)>1

[gmlxf]

create table tableA(field1 varchar(10),field2 varchar(10),field3 varchar(10))
insert tableA
select 'a','b','333'
union select 'a','b','3523'
union select 'a','bb','8'
union select 'c','d','38933'
union select 'c','d','8393'
union select 'e','f','983'
union select 'ee','ff','9843'
union select 'ee','ff','98473'

select * from tableA

select * from tableA a
where (select count(*) from tableA where field1=a.field1 and field2=a.field2)>1

drop table tableA

[dddd8888]

谢谢各位

[dddd8888]

贴子回复次数大于跟给分次数

[dddd8888]

我给不了分，稍等一下