DELETE FROM emp WHERE ID NOT IN (SELECT MIN(ID) FROM emp GROUP BY FName)
delete from tableName where UniqueColumn NOT IN (select MIN(UniqueColumn) from tableName GROUP BY DuplicateRecoedColumn/DeletedDuplicateColumn)
delete from tableName where UniqueColumn NOT IN (select MIN(UniqueColumn) from tableName GROUP BY DuplicateRecoedColumn/DeletedDuplicateColumn)