I am making a custom counter as a wordpress plugin and I hav a little problem with $wpdb
This is the query that fails:

```
private function getMedlemmerfromDB(){
    global $wpdb, $table_prefix;
    $wpdb->plugin_medlemsteller = $table_prefix . "plugin_medlemsteller";
    $fromdb=$wpdb->get_var("SELECT medlemmer FROM $wpdb->plugin_medlemsteller WHERE mID=(SELECT MAX(mID) FROM $wpdb->plugin_medlemsteller)");
    return $fromdb;
}

```

i do not know what $table\_prefix is set to. just hoping it's empty.

in my widget function:

```
public function widget( $args, $instance ) {
        $medlemmer=getMedlemmerfromDB();
             ...

```

This fails, and the plugin (witch is still active) doesn't show.

The query works fine, but when I implement it in my plugin it causes the widget to crash.

Hope some one can help me out.

-Krister