Resolving divergent alembic migrations

[bendnorman]

What is our strategy for resolving divergent alembic migrations when we merge main into a feature branch? I see three options:

1. Whenever there are divergent heads, remove all migration versions and create a new migration that recreates all metadata.
2. Remove and recreate the migrations created on the feature branch.
3. Merge the migrations using alembic branch merges.

Option three feels like the "right" way to resolve divergent migrations, though it might create some additional complexity when we don't really need a full migration history. Option 1 seems like the simplest option but would require contributors to delete their PUDL database and rerun the alembic upgrade head. Maybe that's not a huge issue because it doesn't take that long to repopulate the database.

I think I prefer option 1 because it is the simplest. Maintaining a full migration history doesn't provide much benefit to us.

[zaneselvans]

I also vote for option 1, but I also delete my DB almost every day, sometimes multiple times. One can also repopulate the outputs by pulling down the nightly build outputs if you're just working on changing a single asset or a small group of assets.