Naming conventions for Code First migrations

问题:

We are using code first migrations to keep our database and model in sync. At the moment we have the version number as name for the migration which clearly doesn't work out. The problem is that multiple migrations with the same name where created by different developers independent of each other for their local database. This led to some weird behavior as the IMigrationMetadata.Id was different because of the time stamp but the classes are partial with the same name.

What is the way to go to call these migrations? The examples are always ridiculously oversimplified: e.g. adding a property Readers result in migration AddReaders.

Or should the migrations be broken down to these little changes? Instead of having accumulate all the changes into one big migration. What if there are dependencies?

回答1:

Yes, I think the best way is to break down changes to small units, with descriptive names. As with git, where you should commit often, with migrations you should migrate often. Not necessarily property by property, but containing a logical unit of work.

Like if you need to add two tables for some feature, add those two tables in one migration. Avoid making big migrations where your work for days changing models before creating a migration. Time is essential with avoiding conflicts.

If there are dependencies, one migration should contain related changes, so if another developer applies the migration, the application still works.

When a developer makes a migration, it should be immediately committed and synced (shared with other devs, in case you are not using git).

When you work with small units of change, merging and resolving conflicts becomes much easier.

回答2:

I have been struggling with the same problem and trying out different solutions. What we have come up with so far is to have all the developers exclude the migrations from the check in process and then have one designated developer do the "release migration" that includes the changes from all the others working on the project.