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by _acco 994 days ago
Any ideas for a simple polling implementation that's more robust?
3 comments

It's not exactly simple as it involves some postgres specific knowledge, but you can make it reliable when working with transaction ids (see https://event-driven.io/en/ordering_in_postgres_outbox/).
I've had pretty much the exact same problem and what I went for in my low-volume case was to simply add advisory locks such that I can guarantee the transaction start times provide correct ordering.
Set the trigger to add the primary key + change time to a separate table, then scan/truncate that table to poll changes.