Rails will save associations by default.
If you build an in-memory representation of a record that’s not intended to be saved with a call to
update you need to do one of two things.
- Set autosave to false. Example:
has_one :other_thing autosave: false.
- Don’t associate the built record with the object you’re saving
This default behavior manifested itself because I was doing something of the form:
class Thing has_one :other_thing # 1. Use autosave: false def optimistic_version_of_other_thing OtherThing.new(thing: self) # 2. don't associate the record with self end end thing = Thing.last thing.optimistic_version_of_other # I don't want this persisted thing.update(anything: "else")