add_action('admin_menu','add_hub_page_menu');
add_action('load-edit.php', 'filter_hub_pages_mysql_action');

function add_hub_page_menu(){
    add_pages_page('Hub Pages', 'Hub Pages', 'manage_options', 'edit.php?post_type=page&page_template=hub_template');
}

function filter_hub_pages_mysql_action() {
    if ($_GET['post_type'] !== 'page') return;
    switch($_GET['page_template']){
        case 'hub_template':
            add_filter('posts_where', 'hub_pages_where_filter' );
            add_filter('posts_join', 'join_filter' );
            break;
        default:
            break;
    }
}

function hub_pages_where_filter($sql) {
    global $wpdb;
    $sql = " AND $wpdb->postmeta.meta_key = '_wp_page_template' AND $wpdb->postmeta.meta_value LIKE 'hub-template.php' " . $sql;
    return $sql;
}

function join_filter($sql) {
    global $wpdb;
    $sql = " JOIN $wpdb->postmeta ON $wpdb->posts.ID = $wpdb->postmeta.post_id " . $sql;
    return $sql;
}