http://netinial.com/blog/wordpress/get_post_meta_multiple-pagination-and-ordering

WordPress get_post_meta_multiple, Pagination and Ordering.

Dealing with wordpress.

Because of seo power of wordpress almost every my project I’m using wordpress.
According to me wordpress is single but powerful framework.

Maybe you already know about Custom Field Taxonomies in wordpress.
It was pretty simple Custom Field Filter plug in.

I use it lots of project that I manage.
And also I was pretty happy with this plug in.

But after that 1.4 version they changed their direction of Custom Field Taxonomies from custom fields to tags.

As Custom Field Taxonomies alternative I searched near all of web.

Found 3 function as alternative.

wordpress -> query_posts() was good function. But not supporting multiple filters.

I found get_post_meta_multiple function thanks to the Jamie.

and get_post_meta_multiple (modified version of first) thanks to the Matt

Matt’s function was almost near the function that I looking for. But it was not supporting Order by, Order as, and Pagination also some problems about null category.
You can see both pages people are asking about these, (me to )

I took some help from codes of Jignesh Patel he has also another code to Pagination but I do not like it. to complicated.

Lastly I modified all of them (spend two days on it)

Hope to helps someone.

usage

<?php
$aMetaDataList = array('type' => 'Flat', 'for' => 'Sale');
global $resultList;
    $szCategory = 'NULL'; // All Categories will be shown, $szCategory = '1,2,3'; Only from 1,2,3
    $ppp = 5; // Post per page.
    $metaKey = 'total_property_size'; // Metakey to order.
    $orderBy = 'desc'; // orderBy = 'asc'; for Ascending
    $orderType = 'numerical'; // Order as Numerical, $orderType = 'Aphabetical'; Leave Blank Alphabetical
    $resultList = get_post_meta_multiple( $aMetaDataList, 'post', $szCategory, $ppp, $metaKey, $orderBy, $orderType);
?>

function comes here.

<?php 
function get_post_meta_multiple( $aMetaDataList = array(), $szType = 'post', $szCategory = NULL, $ppp, $metaKey, $orderBy, $orderType)
{
    /**
     * @author Modified by Deniz Netinial.com
     * @copyright deniz [at] porsuk dot net
     * to modify I spend 1 week on it.
     * If you like this modification just send me an e mail, with thanks. SQL_NO_CACHE
     */

    global $wpdb,$wp_query;
    $szQuerystr = "SELECT SQL_Calc_Found_Rows $wpdb->posts.* FROM $wpdb->posts ";

    if ( $szCategory != NULL AND is_string($szCategory) )
    {
    $szQuerystr .= " INNER JOIN $wpdb->term_relationships ON ($wpdb->posts.ID = $wpdb->term_relationships.object_id) ";
    $szQuerystr .= " INNER JOIN $wpdb->term_taxonomy ON ($wpdb->term_relationships.term_taxonomy_id = $wpdb->term_taxonomy.term_taxonomy_id) ";
    }
    $szQuerystr .= " JOIN $wpdb->postmeta on ($wpdb->posts.ID = $wpdb->postmeta.post_id) WHERE ";

    if ( $szCategory != 'NULL' AND is_string($szCategory) )
    {
    $szQuerystr .= " 1=1 AND $wpdb->term_taxonomy.taxonomy = 'category' ";
    $szQuerystr .= " AND $wpdb->term_taxonomy.term_id IN(".$szCategory.")  AND ";
    }

    $szQuerystr .= " $wpdb->posts.post_type = '".$szType."' AND $wpdb->posts.post_status = 'publish'";

    if($metaKey){
    $szQuerystr .= " AND $wpdb->postmeta.meta_key = '".$metaKey."' ";
    }

    $aInnerqry = array();

    if(!empty($aMetaDataList))
    {
        $szQuerystr .= " Group By  $wpdb->posts.ID Having ";
        $szQuerystr .= " $wpdb->posts.ID IN (";
        $szQuerystr .= "SELECT $wpdb->postmeta.post_id FROM $wpdb->postmeta WHERE ";
        foreach($aMetaDataList as $szKey => $szValue)
        {
        $aInnerqry[] = $wpdb->prepare( "(meta_key = %s AND meta_value = %s)", $szKey, $szValue );
        }
    $szQuerystr .= implode(" OR ", $aInnerqry);
    $szQuerystr .= " GROUP BY $wpdb->postmeta.post_id ";
    $szQuerystr .= " HAVING count(*) = " . count($aMetaDataList)." ) ";
    }

    if(strtolower($orderType) == 'numerical')
      { $orderType = 'ABS'; }
    else { $orderType = ''; }

    if(!empty($aMetaDataList)) { $szQuerystr .= " ORDER BY ".$orderType."($wpdb->postmeta.meta_value) "; }
    else {  $szQuerystr .= " ORDER BY $wpdb->posts.post_date "; }

    if($orderBy == strtolower('desc')){ $szQuerystr .= " desc "; }else{ $szQuerystr .= " asc "; }

     # put limit in query built above */

    $aMetaResults = $wpdb->get_results($szQuerystr, OBJECT);

    if(!$ppp or !is_int($ppp))
    { $ppp = intval(get_query_var('posts_per_page')); } //12 posts per page you might use $ppp = intval(get_query_var('posts_per_page'));

    $wp_query->found_posts = count($aMetaResults);
    $wp_query->max_num_pages = ceil($wp_query->found_posts / $ppp);
    $on_page = intval(get_query_var('paged'));
    if($on_page == 0){ $on_page = 1; }
    $offset = ($on_page-1) * $ppp;

    $wp_query->request = $szQuerystr." LIMIT $ppp OFFSET $offset ";
    $pageposts = $wpdb->get_results($wp_query->request, OBJECT);

    echo mysql_error();

    echo ' --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- '.$szQuerystr;

    return $pageposts;
}
?>

and the loop

<?php
if ($resultList):
//Loop through each result post to display appropriate contents
$i = 0;
foreach ($resultList as $post):
	setup_postdata($post);
        echo '<h1>'.$resultList[0]->ID.'</h1>';
endforeach;
?>

Here is the second version of this codes.