select Column1, Column2, count(*)
from yourTable
group by Column1, Column2
HAVING count(*) > 1
select * from (
SELECT id,
ROW_NUMBER() OVER(PARTITION BY column1, column2 ORDER BY id asc) AS Row
FROM tbl
) dups
where
dups.Row > 1
select * from yourTable ou
where (select count(*) from yourTable inr
where inr.sid = ou.sid) > 1