Question

I have a microsoft sql 2005 db table where the entire row is not duplicate, but a column is duplicated.

1 aaa
1 bbb
1 ccc
2 abc
2 def

How can i delete all the rows but 1 that have the first column duplicated?

For clarification I need to get rid of the second, third and fifth rows.

Answer 1

Try the following query in sql server 2005

WITH T AS (SELECT ROW_NUMBER()OVER(PARTITION BY id ORDER BY id) AS rnum,* FROM dbo.Table_1)
DELETE FROM T WHERE rnum>1