Part of me suggests not to do it, as it'll break SQLite compatibility (in MediaWiki SQLite will usually work fine in place of MySQL with some avoidance of certain syntax).

Having said that, the table as currently is wouldn't actually work with the PRIMARY KEY being where it is.

The question I guess, is do we move the PRIMARY KEY upto the id line, and then keep the index where it is to allow SQLite compatibility for little cost, or combine the 2 and have it as a MySQL targeted file?