SQLAlchemy bad error handling

[Robin-Van-de-Merghel]

SQLAlchemy doesn't give us the right "confort" for error handling. We need to handle it depending on which db engine we are using, and we need to use test like "text in the error detail" in e.details. For later, we'll need to find a better way.

Context from PR

If we check if an error is an instance of another module pymysql we could potentially catch some errors as code that are specific on a db. And even with that, I saw errors where people had to use both IntegrityError from sql-alchemy and pymy integrity error because of a bad handling..

It is not pretty, and you can read this response: https://stackoverflow.com/a/70714697

Originally posted by @Robin-Van-de-Merghel in #421 (comment)

[fstagni]

I tried to look into sqlalchemy's github to see if by chance this is an open issue for them. No luck. And maybe it won't ever be on their agenda.

[Robin-Van-de-Merghel]

We can maybe make our own abstraction depending on our needs (our engines)? (I think at least one person did it already)