Thread:Project:Support desk/Database error after updating to 1.21.1/reply

It's not necessary to update from version to version (unless your wiki is too old). But anyway. It's not clear from your message if you unpacked the new MediaWiki installation on top of the older installation or in a new (clean) directory. Unpacking over an old installation can cause errors because of conflicts with old files that shouldn't be there anymore, so I suggest trying to unpack 1.21 on an empty directory and then copy the required files from the old one (see Manual:Upgrading for details)

The field rc_moved_to_ns was removed from recentchanges table on 1.21, and it shouldn't be used anymore. Are you using any outdated extensions? Uninstall/Disable all extensions and try again.