How to order a custom WordPress Post Type by a custom numeric field

So, you need to order a custom WordPress Post Type by a custom numeric field – how?

The Problem

You have a WordPress custom post types, and you need to order by a custom numeric field – how do you do that?

The Cause

You would think that it would be relatively simple, for example the below should work

<?php $loop = new WP_Query( array( 'post_type' => 'staff-member',

'posts_per_page' => 100, 'order' => 'ASC', 'orderby'	=>

'meta_value', 'meta_key' 	=> 'OrderByField','type' => 'numeric' ) ); ?>

But ‘OrderByField’ is treated as a text field, and the number 10, comes after 1, not 2.

The Solution

Use the magic keyword meta_value_num, so your WP_Query would look like this

<?php $loop = new WP_Query( array( 'post_type' => 'staff-member',

'posts_per_page' => 100, 'order' => 'ASC', 'orderby'	=>

'meta_value_num', 'meta_key' => 'StaffOrderBy',

'type' => 'numeric' ) ); ?>

the _num makes all the difference - WordPress will treat it as a numeric field.