I like bugs. Probably not as much as Valerii Kravchuk (http://mysqlentomologist.blogspot.com/) a former colleague of mine who posted about MySQL bugs for a long time, but I still like bugs. I like finding bugs, I like fixing bugs, and I like analyzing bugs.
While I work on the WARP storage engine, I am filing bugs and feature requests for issues I find with MySQL. I also like to comment on MySQL bugs in the bug database to help the MySQL engineers find root causes, and to help end users with workarounds, or explaining misconceptions as to why something may not be a bug. So here are a few interesting bugs I have encountered recently.
Optimizer gives bad estimates for ICP query plans resulting in FTS: