Upserting using insert on conflict

I was looking into upsert for something I am working on and noticed that it is actually a find followed by create or update rather than a "true" upsert. This means it is prone to race conditions as we may have inserted a conflicting record between the find and the subsequent action.

For my use-case ideally I want to use INSERT ... ON CONFLICT UPDATE SET foo=$1 to do the upsert in a single query. The downside is that we wouldn't run any of the after callbacks as we will no longer know whether it was an update or a save. This matches the behaviour provided by other frameworks like Rails (https://apidock.com/rails/v6.0.0/ActiveRecord/Persistence/ClassMethods/upsert).

Looking for feedback whether this change would be accepted into Avram and along those lines should it replace the existing upsert method (although this would be a breaking change due to callbacks) or be a new API entirely?

Start by reading Avram’s existing upsert method and its callback behavior, then compare that flow with the proposed PostgreSQL INSERT ... ON CONFLICT UPDATE query. Done requires an agreed API direction, including whether this replaces upsert or becomes a new method, and defined callback behavior.