Specify stricter database version

[martinheidegger]

Currently the mysql database version is 5 which when resolved to 5.0 is certainly too low (it resolves to 5.7.30 at the time of writing). It would probably better to be stricter with the database version (maybe 5.7? or even with a patch version?) as it would reduce the amount possible bugs.

[MikkCZ]

There was actually an opposite change made since this ticket was reported - 70ba542 set the database container to be used to mysql:latest.

[MikkCZ]

Personally, I agree that the version should be stricter, if possible. At the same time, the Pretalx documentation says

We recommend using PostgreSQL. pretalx also works (and runs tests against) MariaDB and SQLite.

So it might be actually more appropriate to configure Postgres instead.

[rixx]

I have no opinion on this, and am happy to follow whatever people interested in using this dockerfile want – though it would seem to me that changing databases at this point would be a major step for people using this repo, and migrating from one to the other is nontrivial.

[almereyda]

I agree that following the upstream convention seems appropriate for a downstream project. If people need a derivation, they can always go down that path in our magnificient FLOSS land.

Did I understand this correctly: Changing the database (in the main compose.yaml manifest) for people using this repo being a major step implies that people update their local environments usually with git pull and docker compose up -d?

While the migration is not trivial, we can certainly provide different examples through well-documented compose.{postgres,mariadb,mysql}.yaml manifests.

For me this discussion correlates strongly with the observations and argument in #62 (comment) : with adopting more conventional patterns of handling a dockerized Django application, we can reduce the ambiguity for end users of this repository.

The migration path from MySQL to PostgreSQL could be transparent, when this initiative comes to terms:

The Future of MySQL is Postgres

Simplifying Migrations by Reimagining MySQL as a PostgreSQL Extension

Jonah Harris, Postgres Conference, 2024-04-19