optimistic create / update / patch / remove

[ahdinosaur]

example: update

• on start, set optimistic data.
• if complete (success), set real data.
• if error, rollback to previous data.

except when we have multiple concurrent updates:

• keep track of the last real data.
• set any new updates as optimistic data
• only when all updates fail, rollback to previous data.

should probably draw this or something. /cc @pietgeursen

[danalexilewis]

What happens with concurrent updates where one update fails rather then all?

[ahdinosaur]

@agentlewis assuming these updates all reference the same database entity (implicit when i said "concurrent updates" above, but maybe not obvious), i guess it really only matters that the last one succeeds.