How to get categories with posts by custom field value?

Question

I have a big categories tree, around 2000 subcategories, and I have a lot of posts with a custom field city (different values).

I have created filter posts by "city" field. But I have a problem with categories list. I just need to show all categories that have 1+ posts with needed value in the city field.

If I get all categories in an array and check the number of posts by the custom field in each category in a loop - that will create thousands of DB queries. I need a more accurate solution to do this.

Answer 1

try this one..

<div style="display:<?php $meta_city = get_post_meta( get_the_ID(), 'city', true );
            if ($meta_sub_img == '') {
                echo 'none';
            } else {
                echo 'block';
              }
?>;">

<!--- your content --->

</div>