Query to remove duplicate records, in this query please add all the columns in GROUP BY clause that are duplicate, it is based on primary key DELETE from TableName WHERE CoumnName1 + CoumnName2 + CoumnName3 IN (select CoumnName1 + CoumnName2 + CoumnName3 FROM TableName group by CoumnName1 , CoumnName2 ,CoumnName3 having Count(ID)>1) AND ID NOT IN (select MAX(ID) from TableName WHERE CoumnName1 + CoumnName2 + CoumnName3 IN (select CoumnName1 + CoumnName2 + CoumnName3 FROM TableName group by CoumnName1 , CoumnName2 ,CoumnName3 having Count(ID)>1) ...