function videotube_get_total_post_views() {
    global $wpdb;

    $query = $wpdb->get_var( $wpdb->prepare(
        "
        SELECT sum(meta_value)
        FROM $wpdb->postmeta LEFT JOIN $wpdb->posts ON ( $wpdb->postmeta.post_id = $wpdb->posts.ID )
        WHERE meta_key = %s
        AND $wpdb->posts.post_status = %s
        AND $wpdb->posts.post_type = %s
        ",
        'count_viewed',
        'publish',
        'video'
    ) );

    return $query;
}