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by danpalmer 1027 days ago
It means that the `FOR UPDATE` part in `SELECT ... FOR UPDATE` causes a disk write, because it locks that row. It bumps the MVCC metadata, the transaction ID on the tuple I think(?) in order to prevent other transactions from modifying it. While the data hasn't actually changed, the availability of that data has changed, so I think it's reasonable to consider that a write from the database perspective.

Although FWIW, I do completely understand your use-case of trying to quieten down logs for a queue!
1 comments
vermon 1027 days ago
Make sense. I guess it could also be a flag for the audit module where you can toggle if SELECT permission for auditing includes the SELECT clauses that need RowShareLock as well or not.
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danpalmer 1027 days ago
Yes! I don't think that should be a default because I think it's "safer" and more correct to consider locks writes, but having it available for pragmatic use-cases like this would be nice.
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