Medicinal Monks,

When you do

$sql = "SELECT field_1, field_2 FROM myTable";
$sth = $dbh->prepare($sql) or die("Could not prepare!" . $dbh->errstr)
+;
$sth->execute() or die("Could not execute!" . $dbh->errstr);
while (($val_1, $val_2)  = $sth->fetchrow_array()) {
  $myhash{$val_1} = $val_2;
}
$sth->finish;
foreach $val_1 (keys %myhash) {
   print "myhash{$val_1} = $myhash{$val_1}\n";
}
[download]

If, for any record, field_2 was empty, then $val_2 is not set, and the "print" statement throws an error "Use of uninitialized value in concatenation...". A clumsy fix would be

if ($val_2) {
   $myhash{$val_1} = $val_2;
}
else {
   $myhash{$val_1} = '';
}
[download]

but there HAS to be a better way to go about it. Anyone?

Thanks.

---

In reply to Hashing uninitialized values when no value returned from DBI sql select by punch_card_don

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