Jens Frank wrote:

Even worse than the crash recovery issue is the locking of MyISAM databases, which is not very granular. With our change rate, MyISAM is not an option.

Well... we've already established that this would have to live in a separate table, since it would have to be MyISAM. The table doesn't need to be written to for each edit, only when a category is added/changed/deleted from a page, which must be a pretty small subset of edits (wild guess: 10%?), so maybe it's not that big a problem...?

To dig up a little history, the queries I/we have tried on the existing categorylinks table take too long, so we either 1) can't run queries against really big categories or 2) need a separate table/data structure.

Aerik