Miss Dada  🏳️‍⚧️

I want to run multiple test processes against one database. Each process needs to see the database as if it were the only process. Nested transactions (putting the whole test in a transaction) would do it, but Postgres can't do that. Is there another way?

I don't think transactions help at all. The app under test will use transactions. You can't nest transactions in Postgres, so wrapping the whole test run in a transaction would preclude the app's normal use of them.

You can emulate nested transactions with savepoints.

Yeah, but the app already does transactions in the usual way, so I don't think I can do that without modifying the app?

How is the app executing its queries? Are you just using raw SQL? No abstraction layer that can help? (e.g. something like https://github.com/diesel-rs/diesel/blob/master/diesel/src/connection/transaction_manager.rs#L86-L126 …)