IIUC - Does this mean if I am making a network call, or performing some expensive task from within the job, the transaction against the database is held open for the duration of the job?
Definitely not! Jobs in River are enqueued and fetched by worker clients transactionally, but the jobs themselves execute outside a transaction. I’m guessing you’re aware of the risks of holding open long transactions in Postgres, and we definitely didn’t want to limit users to short-lived background jobs.
There is a super handy transactional completion API that lets you put some or all of a job in a transaction if you want to. Works great for making other database side effects atomic with the job’s completion. https://riverqueue.com/docs/transactional-job-completion