[debian-mysql] FWD [Re: Bug#860970: release-notes: MariaDB vs MySQL section 2.2.3 needs clarifying on how to perform the upgrade]

[Andreas Beckmann]

> Otto, are you now saying that without any action, mysql-server-5.x will
> be upgraded to mariadb-server-10.1? If that is true, could that be made
> more explicit in the text? If that isn't true, can it be made more
> explicit when the system administrator is supposed to install
> default-mysql-server during upgrades (that is what I tried to accomplish
> in my "improvement")?

>From my experience with piuparts:
If there is no Depends: mysql-server in jessie (and no Depends:
default-mysql-server in stretch), but the database is only pulled in via
Recommends (or Suggests or even only manually), it is likely that
mysql-server-5.5 gets removed during the dist-upgrade, without a
replacement getting installed. mysql-server-5.5 *cannot* survive the
upgrade to stretch due to Breaks/Conflicts somewhere (could have been
libstdc++v5 or mariadb-client or ...) - even if *no* mariadb-server gets
installed.

In piuparts mysql+postgres are the only services that are allowed to be
started in a chroot - because that is often more useful than testing for
behavior without a database running ...
In piuparts I have a hardcoded list of packages that benefit from a
database server (but only recommend it), and that server gets installed
before that packages to be tested (s.t. it is running at test-package
install time).
piuparts usually runs a single pass apt-get dist-upgrade (no apt-get
upgrade first), with the exception of database servers being upgraded
first (s.t. the new database is running before the database users get
upgraded). Otherwise database users that don't depend on a server
usually get configured (and fail) while the database server has not been
started again.
For stretch I also maintain a hardcoded list of packages where I need to
install default-mysql-server "manually" during the upgrade from jessie,
since the decision was not to have an automatic migration from
mysql-server to default-mysql-server if that was only manually installed
by the admin.

Andreas