Make division in post_query?

Question

I am new to both PHP and WP so I am struggling with one thing:

I want to fetch all my post and then order it according to my meta-value "_mycounter" divided with the date in seconds from 1970 or what ever it was.

I know 'orderby' => 'meta_value_num / date' is not right but how can I solve this? Is there anyway to add division/multiplication calculation in the way I am asking for?

$query = array(
  'orderby' => 'meta_value_num / date', 
  'meta_key' => '_mycounter',
  'order' => 'DESC'
);
query_posts($query); 

Answer 1

MySQL can do math but can't pass it through query_posts like that, or any WordPress' post query functions, which depend upon WP_Query. They will literally look for a table/column named, in your case, "meta_value_num / date". To do it in SQL I believe-- aka., this is untested-- you'd have to do something like this:

SELECT (meta_value_num / DATE()) as ddiv
FROM <some-table>
ORDER BY ddiv

And that isn't going to be a very efficient query anyway.

Why can't you do the division after the query? I believe the sort order will be the same either way.