my $sth = $dbh->prepare(qq{SELECT `id`,`rec` FROM `memrecs`});
$sth->execute();
while(my ($_id,$_rec) = $sth->selectrow_array()) {
 if($_rec =~ /A .. Z/) {
   $_rec =~ tr/A-Z/a-z/g;
   $dbh->do(qq{UPDATE `memrecs` SET `rec` = ? WHERE `id` = ?}, undef, "$_rec", "$_id");
 }
}
$sth->finish();