Wordpress meta query

Use below code will work as per your scenario.

add_filter( 'pre_get_posts', 'filterReports' );function filterReports( $query ) {  if( is_post_type_archive( 'reports' ) && $_GET['top'] ) {     $reports_meta_query = $query->get('meta_query');     //Add our meta query to the original meta queries     $reports_meta_query[] = array(                    'key'=>'count',                    'value'=> 4,                    'compare'=>'>=',                );     $query->set('meta_query',$reports_meta_query);     // somehow construct a query that checks if sum / count >= 4  }}

Pretty sure the query you are looking for is something like this:

SELECT  sum.post_id, sum.meta_value, count.meta_value, (sum.meta_value / count.meta_value) as result  FROM     wp_postmeta sum  LEFT JOIN wp_postmeta count USING(post_id)  WHERE    sum.meta_key = 'sum' AND    count.meta_key = 'count'  HAVING     result >= 4

You are basically joining twice the same table based on the post_id, so you can then query by the meta_key of both sum and count, then you look for the result of your math in a Having clause to check if the result would be bigger than 4 as requested.

Hope with this you can get what you were looking for.

Cheers