my $sql_select = "select * from $tableName";


 	$sth->execute or die $sth->errstr;


 	
        $sql_delete = "delete from $tableName where LiftChr=? and LiftPos=?";


 	my $sth1 = $db->prepare($sql_delete);

 	



 	while ($snp = $sth->fetchrow_hashref) {

	
          $sth1->execute($snp->{'LiftChr'}, $snp->{'LiftPos'});
	}