How to overwrite migrations after toVersion 2?

[samuelbeers]

Hello, I have just a couple clarifying questions about using migrations for the first time

1. When I want to make new migrations, but I've already done one before, do I just overwrite whatever I had written previously in the migrations file?
2. I know deletion / renaming isn't supported yet. If I need to delete / rename a table, would my data be lost for just those tables or for the entire database?