I’ve been working on tuning aggregate views with a test copy of a large ASO cube to which I added some additional dimensions. Tuning aggregate views can be tricky, because aggregate views make query performance heavily dependent on the exact combination of levels being queried. And there’s always some user that comes along with an unusual query that happens to hit a combination of levels that performs particularly poorly. So when I handed the system over for front-end certification by users, I enabled query logging. By parsing the log for “worst case” query times, I could proactively monitor and then investigate any particularly nasty cases the users encountered. Unfortunately, I was being a little bit too smart for my own good.