I tried to do an upgrade of my Mediawiki site from 1.4.1 to 1.5.5. Luckily, I decided to test before I did this on my live site. Here is what I did:
1. Setup Apache, MySQL, and PHP on my local workstation. 2. Imported live database into my local workstation's MySQL. 3. Copied MediaWiki 1.5.5 files to local Apache htdocs directory. 4. Ran the install/config script and pointed it to local copy of database. The script saw the database tables and performed an upgrade on the tables as needed. 5. Copied LocalSettings.php to main directory. 6. Opened my upgrade local mediawiki site.
Everything looked OK at first glance. However, when I browsed some of the pages, I noticed they were several months old. I checked the "Recent Pages" and it showed that I made edits in the past week, but when I clicked on the diff link and looked at those, it displayed old data as well. Finally I used SQLyog to open the database directly and look at the tables. in the wiki_cur table I can see the latest edits and it has the correct data there.
Is there something obvious I am missing?