sub FetchText {
  # doing something like this:
  # $sth->fetchrow_array("SELECT id_txt, txt FROM Text");
}
($,, $\) = ("\t", "\n");
open I, ">iWords.txt" or die $!;
open V, ">Vocab.txt"  or die $!;
while (($id, $_) = FetchText()) {
    $_=lc;
    print I $id,$word{$_}||=(print(V $_,++$w),$w)
        for /\b[a-z]{3,30}\b/g;
}
close I;
close V;