Like I said earlier, every tiny change that the test suite reveals after code changes is significant. I caught a very subtle “bug” today in recent changes to mk-query-digest (a.k.a. mqd). If you like to read about subtle bugs, read on.
An mqd test on sample file slow023.txt began to differ after some
pretty extensive code changes of late:
< # Query 1: 0 QPS, 0x concurrency, ID 0x8E38374648788E52 at byte 0 ________
> # Query 1: 0 QPS, 0x concurrency, ID 0x2CFD93750B99C734 at byte 0 ________
The ID which depends on the query’s fingerprint has changed. It’s very important that we don’t suddenly change these on users because these IDs are pivotal in trend analyses with mqd’s
--review-history option. First some background info
on the recent code changes and then the …