Feature Request: differentiate between update and create in upsert

[matthiasdg]

Currently upsert will always create new entities if you supply the required fields (in lots of our tables only an id is needed and nothing more).
It would be nice if we could supply additional headers (or a flag) for the
If-Match: * header (or the If-None-Match: * but then you could also use create) to limit this cf. https://learn.microsoft.com/en-us/power-apps/developer/data-platform/use-upsert-insert-update-record?tabs=webapi

[MarcusRisanger]

Hi there!

I could take a look at adding a options in the upsert method for these headers. Would have to do some testing to see how the current API handler behaves in practice with partial "failures" :)

You are also welcome to submit a PR!