$sql = "SELECT * FROM sp WHERE NOT EXISTS (SELECT * FROM SP,SUPPLIER WHERE SUPPLIER.snum = SP.snum)";
$sth = $dbh->prepare($sql);
$sth->execute
              or die "Error: $DBI::errstr\n";

$sth->bind_col(1,\$spnum);
$sth->bind_col(2,\$snum);
$sth->bind_col(3,\$pnum);
$sth->bind_col(4,\$qty);

while($sth->fetch){

     $sql = "INSERT INTO sp_err SELECT * FROM sp WHERE spnum = $spnum && snum = $snum";
     $sth = $dbh->prepare($sql);
     $sth->execute
             or die "Error: $DBI::errstr\n";
     print "deleted row";

        
 }