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How to find duplicates

Author

Topic

nicky_river
Yak Posting Veteran

55 Posts

Posted - 2010-10-18 : 08:28:35

How do i only find duplicate records in a table, which is given below.

A B
1 abc
1 def
1 ggg
2 serg
3 awer

pk_bohra
Master Smack Fu Yak Hacker

1182 Posts

Posted - 2010-10-18 : 08:41:18

By record i understand all the selected columns.
In the data posted by you I don't see any duplicate records.

To start with:

Select <columns >
From <your table>
Group by <Columns selected in select statement>
Having count(*) >1

webfred
Master Smack Fu Yak Hacker

8781 Posts

Posted - 2010-10-18 : 09:29:15

select * from table
where id in (select id from table group by id having count(*) > 1)

No, you're never too old to Yak'n'Roll if you're too young to die.

shaggy
Posting Yak Master

248 Posts

Posted - 2010-10-18 : 11:26:27

declare @t table (col1 int)

insert @t

select 1
union all
select 1
union all
select 2
union all
select 3
union all
select 4
union all
select 5
union all
select 5
union all
select 6
union all
select 7
union all
select 8

select col1 from (
select ROW_NUMBER() over (partition by col1 order by col1) rno,* from @t )a
where rno > 1

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