for ( keys %{$self->{SQL}} ) {
  my $name = $_;
  my $dbh = $self->{DBO};
  my $sth = $dbh->prepare($self->{SQL}{$name};
  $self->{STH}{$name} = sub {
    my @res;
    $sth->execute(@_);
    while (my $dbrow = $sth->fetchrow_hashref()) {
      # Not sure why you're making a reference to a hashref here
      push @res, \$dbrow;
    }  
    return \@res;
  };
}