For the db question when spinning up the Core server it defaults to using Postgres so if you wanted to use MySQL you may have to do some extra configuration in order to get it to work. The process uses
alembic for migrations so if that works against MySQL I don’t think it would be unreasonable. (I only have experience using it with Postgres so I’m not too sure on the trade offs)
Prefect flows can be triggered based on events!
Calling the API to trigger a flow run would be how you would do it. There is also a task in the task library for
starting new flow runs (or you can roll your own 🙂) which could be used to trigger a new run based on some upstream state.