I was wondering if there were any efficient way of fetching all user comparing two different meta_key. I am currently fetching all user compared to the first meta, then loop trough the user_id to compare the other meta. I actually need to count how many user have both values. Ex : 'MRC' => 'Mitis' AND 'sellable_online' => 'true'
Using the same structure as a meta_query, you can define a relationship to 'AND', but I think that's already the default. Please post a more structured example of your code so we can help you better. http://codex.wordpress.org/Class_Reference/get_users