my $query = "SELECT location FROM demstock2 WHERE ds_id=$main";
my $sth   = $db->prepare($query);
$sth->execute or print "Can't execute <pre>$query</pre>: " . $db->errstr . "<br>\n";

##</code><code>##

my $query = "SELECT location FROM demstock2 WHERE ds_id=?";
my $sth   = $db->prepare($query);
$sth->execute( $main ) or print "Can't execute <pre>$query</pre>: " . $db->errstr . "<br>\n";

##</code><code>##

my %actions = { 'BOND'=>\&do_bond,
                'SHARE'=>\&do_share }
if ( exists $actions{ $action } ) {
   my $err = &{ $actions{ $action } };
   if ( $err ne '1' ) {
      print $err;
   }
} else {
   print "Action is not defined.";
}

##</code><code>##

sub do_bond {
   get LOCATION;
   check LOCATION or return;
   foreach @acc
      check PARENT_ID or return;
      update & insert or return;
   foreach @built
      check PARENT_ID or return;
      update & insert or return;
   return 1; # if you got here, everything's fine
}

##</code><code>##

sub do_bond {
   get LOCATION;
   check LOCATION or return;
   foreach @acc
      check PARENT_ID or { set error; next; }
      update & insert or { set error; next; }
   foreach @built
      check PARENT_ID or { set error; next; }
      update & insert or { set error; next; }
   return 1; # if you got here, everything's fine
}