I just deleted over a million worth of backlinks from our database, namely all becklinks from 2002. Our policy of keeping per-story backlinks forever just did not work out - the accesslog table is (or was) one of our biggest headaches. It causes a lot of the slow queries for MySQL, and when I checked I found it was corrupt again today. I think in the future we'll have to adopt a different policy of keeping story backlinks for a month or two, max.

During the time MySQL took to delete the records, access to individual stories timed out because the the table was locked. Sorry for that outage and the ones before which were caused by other db maintainance work.