Question

For my database project, I am using SQL Alchemy. I have a unit test that adds the object to the table, finds it, updates it, and deletes it. After it goes through that, I assumed I would call the session.rollback method in order to revert the database changes. It does not work because my sequences are not reverted. My plan for the project is to have one database, I do not want to create a test database.

I could not find in the documentation on SQL Alchemy on how to properly rollback the database changes. Does anyone know how to rollback the database transaction?

Answer 1

Postgres does not rollback advances in a sequence even if the sequence is used in a transaction which is rolled back. (To see why, consider what should happen if, before one transaction is rolled back, another using the same sequence is committed.)

But in any case, an in-memory database (SQLite makes this easy) is the best choice for unit tests.