Compare two meta key values against each other inside the get_posts array?

Question

I'm banging my head to the wall all day trying to figure this out.

I have two meta keys a1 and a2 with numbers inside.

I'm trying to show posts that are a2 > a1.

In a nutshell, here's what I'm trying to accomplish:

    $posts = get_posts(array(
        'post_type'         => 'post',
    
    
        'meta_query' => array(
//return both meta keys       
            array(
                'key'            => 'a1',
            ),
            array(
                'key'            => 'a2',
            ),
//only show posts that a2 meta_value is greater than a1  meta_value
            'a2' > 'a1'
        ),
        
    ));

I know it should be possible to do this somehow.

I'm not the only one in the world trying to compare whether one post's meta_key value is greater than other...

Desperately need help or any kind of solution.

Answer 1

You can't do this in the meta query I'm afraid.

You'd need to get all the relevant records in meta query, then make that comparison inside PHP, to filter out the records you don't need.