Query_posts with custom field meta value

Question

I have these requirements:

• If the child page has featured_product and the value equals to 1 then it's featured. This works.

• If the child page has featured_product and the value does not equal to 1, or if it doesn't even have the field featured_product then it's not featured product. This doesn't work at the moment.

For featured products (it works):

<?php 
    query_posts(
        array(
            'showposts'   => -1, 
            'post_parent' => $post->ID, 
            'post_type'   => 'page', 
            'orderby'     => 'title',
            'order'       => 'ASC', 
            'meta_key'    => 'featured_product', 
            'meta_value'  => 1
        )
    );
?>

For normal product (it doesn't work):

<?php 
    query_posts(
        array(
            'showposts'    => -1, 
            'post_parent'  => $post->ID, 
            'post_type'    => 'page', 
            'orderby'      => 'title', 
            'order'        => 'ASC', 
            'meta_key'     => 'featured_product', 
            'meta_compare' => '!=', 
            'meta_value'   => 1
        )
    );
?>

Answer 1

The best solution i found for querying posts where the meta_key IS NOT or doesn't exists is to use the posts_where filter with a small sub-query, try this:

//paste this function in your theme's functions.php

function metakey_no_featured( $where )
{
    global $wp_query;
    global $wpdb;
    $where .= $wpdb->prepare(" AND $wpdb->posts.ID NOT IN ( SELECT post_id FROM $wpdb->postmeta WHERE ($wpdb->postmeta.post_id = $wpdb->posts.ID) AND meta_key = %s AND meta_value = 1) ",'featured_product');

    return $where;
}


//and when you query none featured products use
add_filter('posts_where', 'metakey_no_featured' );
query_posts(
        array(
            'showposts'    => -1, 
            'post_parent'  => $post->ID, 
            'post_type'    => 'page', 
            'orderby'      => 'title', 
            'order'        => 'ASC', 
        )
    );
remove_filter('posts_where', 'metakey_no_featured' );