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by ChrisAtWork 3624 days ago
I don't think I've ever seen delta's done at-scale with actual temporal tables, but rather with transaction Id's of some sort.

For example (based on the doc) when you register a delta link, there's a row written to Azure Tables saying, "owner:iheart2code, deltaToken:foo, lastRecordIdSeen:123".

When you then make the Delta request, we look up "foo" for you, find that the last id you've seen is 123, and then only give you records from the transaction table with an id larger than that.

Temporal is always a can of worms, as clocks are impossible to keep in sync and there are endless race conditions.

Making the delta tokens causal, rather than temporal, is the way to go. Anything else is brutal in the distributed systems world...