modify-wp-query.php

<?php
/**
 * Modify WP_Query to return taxonomy fields in post array
 * 
 * @author Jess Green <jgreen AT psy-dreamer.com>
 */
add_filter('posts_orderby', 'taxonomy_orderby');
add_filter('posts_fields', 'taxonomy_archive_select_fields');
add_filter('posts_join', 'taxonomy_archive_join');
    
/**
 * Change orderby parameter for archive-specific loop
 * 
 * @access private
 * @global wpdb $wpdb WordPress DB object
 * @param string $order_by
 * @return string
 */
function taxonomy_orderby($order_by)
{
    global $wpdb;
    
    $order_by = "{$wpdb->term_relationships}.term_taxonomy_id, {$order_by}";
    
    return $order_by;
}


/**
 * Add fields to SELECT list for loop
 * 
 * @access private
 * @global wpdb $wpdb
 * @param string $fields
 * @param WP_Query $query
 * @return string
 */
function taxonomy_archive_select_fields($fields, WP_Query $query = null)
{
    global $wpdb;

    $fields .= ", {$wpdb->terms}.term_id AS term_ID, {$wpdb->terms}.name AS term_name, {$wpdb->terms}.slug AS term_slug";

    return $fields;
}


/**
 * Add new INNER JOIN call for forcing taxonomy name and slug to end of post objects
 * 
 * @access private
 * @global wpdb $wpdb
 * @param string $join
 * @return string
 */
function taxonomy_archive_join($join)
{
    global $wpdb;   
 
    $join .= " INNER JOIN {$wpdb->terms} ON ({$wpdb->term_relationships}.term_taxonomy_id = {$wpdb->terms}.term_id)";
 
    return $join;
}