Find and delete duplicate data in the data table

Test successful in Oracle

-- Find the duplicate data in the table select * From vav_groupbrand_casn where ccasn in (select ccasn from vav_groupbrand_casn group by ccasn having count (*)> 1) Order by ccasn

-- Select * From vav_groupbrand_casn A, vav_groupbrand_casn B where a. cgroupbranid = B. cgroupbranid and A. ccasn = B. ccasn and A. ccreatedate> B. ccreatedate

-- Delete duplicate data Delete from vav_groupbrand_casn A where rowid! = (Select max (rowid) from vav_groupbrand_casn B where a. cgroupbranid = B. cgroupbranid and A. ccasn = B. ccasn and A. ccreatedate> B. ccreatedate );