__PACKAGE__->set_sql( retrieve_hash => qq{
    select * from __TABLE__ where id=?
    }, 'Main');

sub retrieve_hash {
  my ($class,$id) = @_;
  my $sth = $class->sql_retrieve_hash();
  $sth->execute($id);
  my $hashref = $sth->fetchrow_hashref();
  $sth->finish;
  return $hashref;
}