sub col_name {
    my $self = shift;

    if (@_) {
        my $data = shift;
        my $sth = $self->result_source->schema->storage->dbh->prepare("update table set col_name = ? where primary_key = ?");
        $sth->bind_param(1, $data, {TYPE => DBI::SQL_BINARY});
        $sth->bind_param(2, $self->primary_key);
        $sth->execute;
    }

    my $sth = $self->result_source->schema->storage->dbh->prepare("select col_name from table where primary_key = ?");
    $sth->execute( $self->primary_key );

    my $result = $sth->fetchrow_hashref;
    return $result->{col_name};
}