Laurenz Albe <laurenz.a...@cybertec.at> writes: > Perhaps it would be good to consider this question: > Do we call something "read-only" if it changes nothing, or do we call it > "read-only" if it is allowed on a streaming replication standby? > The first would be more correct, but the second may be more convenient.
Yeah, this is really the larger point at stake. I'm not sure that "read-only" and "allowed on standby" should be identical, nor even that one should be an exact subset of the other. They're certainly by-and-large the same sets of operations, but there might be exceptions that belong to only one set. "read-only" is driven by (some reading of) the SQL standard, while "allowed on standby" is driven by implementation limitations, so I think it'd be dangerous to commit ourselves to those being identical. regards, tom lane