Unique User Count -- Rollup
3 April 5:30PM - 8:20PM @ Community Networking Welcome Reception
You are combining your logs to find out how many _different_ users have connected. This, itself, is somewhat I/O intensive. But then add to that the desire to rollup daily "uniques", into "weekly" uniques. But you find that SUM(), etc, won't work. I will outline a way to store data at less than one bit per unique user, and do rollups.
MySQL Geek, self
14 years with Yahoo. The go-to guy for performance issues. Major troller of forums.mysql.com.