I recently started getting this message on my WordPress site: http://18.104.22.168
WordPress database error: [You have an error in your SQL syntax. Check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1]
SELECT DISTINCT(post_id) FROM wp_post2cat WHERE category_id=
I'd been cleaning out unused posts, pages and categories. Could this have caused the problem?
In searching the forum I see that there was once a problem when hosts upgrated PHP but didn't upgrade Zend. I don't think that's my problem. My PHP version is 4.3.11 and Zend Opt is 2.5.10.