sql server 2008 删除重复项

Question

我有这样的重复

col1, col2
1, alex
1, alex
2, liza
2, liza
3, peter
3, peter

每个只有两个。我如何删除重复项？

Answer 1

WITH    q AS
        (
        SELECT  *,
                ROW_NUMBER() OVER (PARTITION BY col1, col2 ORDER BY col1, col2) AS rn
        FROM    mytable
        )
DELETE
FROM    q
WHERE   rn >= 2

看这里:

Deleting duplicates