What's a good practice for handling subflow failure? For e.g. I have a case of a flow triggering many (e.g. 15) subflows and one subflow fails.

ive set

return_state

to True. After all the sub flow runs are over, I have codes for exception handling over the sub flows. But you are going to be more specific about your use case.

ive set return_state to True.

Yeah, I do this as well and fetch the result. What's happening is that I have many upserts to do at once to a data warehouse. Each table upsert is one subflow. It would be great if the failed subflow could store the result somewhere such as to an Artifact maybe? Not sure yet. The issue is that it's $ costly to redo the upsert process each time so I'm trying to figure out a way to get the subflow failures and persist those somewhere so that subflow could be retriggered.

Not entirely sure about your usecase. But you could break down the sub flow into multiple task and

cache

your task result?

Caching the subflow results would be like so I guess? https://docs.prefect.io/latest/concepts/results/#caching-of-results-in-memory

I see, thanks so much!