After racking my brain for hours upon hours working for a solution to this:

WordPress database error: [Table ‘triajnamics.trinamicspost2cat’ doesn’t exist]SELECT p2c.category_id AS cat_id, COUNT(p2c.rel_id) AS numposts, UNIX_TIMESTAMP(max(p.post_date_gmt)) + '-4' AS last_post_date, UNIX_TIMESTAMP(max(p.post_date_gmt)) AS last_post_date_gmt FROM trinamicspost2cat p2c INNER JOIN trinamicsposts p ON p2c.post_id=p.id WHERE (p.post_status='publish' OR p.post_status='static') AND p.post_date_gmt<='2007-09-28 03:49:02' GROUP BY p2c.category_id ORDER BY numposts DESC

I realized that creating “dummy tables” was the best way to go. Adding in an old post2 table seems to satisfy Wordpress 2.3. In summary, I thought it was my theme or my webhost, but it was simply Wordpress choking on the table it hastily deletes. If you read the codex forums, they’ll likely drone on about your incompatible plug-ins. For me, and I suspect others, this was not the case.Upgrading? I’d of course back-up your files and database, disable all plug-ins, and upgrade. Check for errors. None? Celebrate. String of errors on index.php? Try adding in an old table from your back-up (whichever one your error messages are referencing).Good luck!