fix(db): Avoid dirty read for local message updates #9424
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Signed-off-by: Christoph Wurst <[email protected]>
6 tasks
miaulalala
approved these changes
Mar 5, 2024
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When updating local messages we diff the recipients and INSERT/DELETE all changes. Afterwards, the current recipients for the updates message are fetched from the database. This is a textbook example of a causal read. It's likely that database clusters with weak consistency read dirty data.
I'm applying the quick and dirty fix here because the operation already happens in a transaction. The better performing fix would be to build the data in memory. We have everything we need and can refactor the SELECT away.