mysql_fetch_field() and mysql_num_fields() Warnings

[BamaStangGuy]

I have been having some problems on a script I am writing for one of my forums. In debug mode when I click explain on the main page of this script I get the errors below for every query I have that isn't a standard vBulletin query, however, all these queries run and produce the desired results.

However on another page, which is suppose to pass the id of a url and then retrieve the results of that id from the database, the query to get the data is not even ran and I am just presented with a warning that a field is missing. Same error when viewing the explain only thing is the query isn't listed as being ran.

I was wondering what are the reasons for the error below to be shown?

Here is one query that produces the following error, as it is run exactly:

PHP Code:

    // Count the total Artists
    $artists_data = $db->query_read("
            SELECT
            COUNT(artistid) AS artists
            FROM " . TABLE_PREFIX . "vblyrics_artists
    ");

    $total_artists = $db->fetch_array($artists_data);
    $totalartists = $total_artists['artists']; 


Warning: mysql_fetch_field(): supplied argument is not a valid MySQL result resource in /home/exforum/public_html/includes/class_database_explain.php on line 94

Warning: mysql_num_fields(): supplied argument is not a valid MySQL result resource in /home/exforum/public_html/includes/class_database_explain.php on line 99

Any help would be great. This is really frustrating me.