Your comment about the MySQL upgrade scripts is on the mark.
I'm not a fan of MySQL and avoid using it whenever possible. The only
reason Gerrit even runs on it is because a few people whined, and I figured
adding the support if they helped maintain it would be easier than telling
them "go install PostgreSQL". Unfortunately the MySQL using crowd doesn't
get around to testing the upgrade scripts until after I've cut a release.
We should start to be improving in the MySQL compatibility area. I'm
unfortunately running a production Gerrit on a MySQL backend now, which
means I now have more personal incentive to validate the upgrade scripts
are syntactically correct.