I’ve developed what appears once again to be a good habit – NOT to upgrade a WordPress instance soon after new [sub-]version release. Wait at least a month.
Indeed, why hurry? I back up both database and file systems regularly and automatically, most inherently insecure features of the system (like user registration) are turned off, Apache’s mod_security is in place…
However, the rule of waiting a month (more is better) for a release to mature resulted in my installation being stuck with some old version of WP (2.2) – they just were updating way too quickly. And I started to feel slow in implementing new features in my blogs. So I took a plunge with WordPress 2.6.
All categories becoming EMPTY-named was the major problem.
David Cumps, a “2.6 categories disaster” pioneer gathered a sizeable crowed of folks reporting the problem of lost categories indicating the problem was huge. The first solution (by David) was manual but it saved some from painful WordPress rollback.
Soon Remy Blaettler offered an elegant solution of 3 SQL queries (you’d have to have your
wp_categories table backed up before upgrade for complete elegance). Notice the 3rd query is in comments and is responsible for restoring categories hierarchy.
Wow! Watch the “rule of month” in action: 2.6 introducing the disaster was released on July 15 with the fix rolled in on Aug 15.
Easy does it.