{
  my %t;
  $t{$_} .= "1" for @tax_ids;
  $t{$_} .= "2" for @db_state;
  @add = grep $t{$_} eq "1", keys %t;
  @delete = grep $t{$_} eq "2", keys %t;
}
[download]

I might have the add/delete pairs backwards there. You jumped from "array 1" to "@tax_ids" in your example. {grin}

-- Randal L. Schwartz, Perl hacker