my $sth = $dbh->prepare($sql);
if (!$sth) {
    die "sth error:" . $dbh->errstr . "\n";
}
if (!$sth->execute) {
    die "sth execute error:" . $sth->errstr . "\n";
}
my $names = $sth->{'NAME'};  # the info you seek
foreach my $name (@{$names}) {
  # do something with the name
}