Re: our checks for read-only queries are not great

On Mon, 2020-01-13 at 13:56 -0500, Stephen Frost wrote:
> > I think that having ALTER SYSTEM commands in pg_dumpall output
> > would be a problem. It would cause all kinds of problems whenever
> > parameters change. Thinking of the transition "checkpoint_segments"
> > -> "max_wal_size", you'd have to build some translation magic into pg_dump.
> > Besides, such a feature would make it harder to restore a dump taken
> > with version x into version x + n for n > 0.
>
> pg_dump already specifically has understanding of how to deal with old
> options in other things when constructing a dump for a given version-
> and we already have issues that a dump taken with pg_dump X has a good
> chance of now being able to be restoreding into a PG X+1, that's why
> it's recommended to use the pg_dump for the version of PG you're
> intending to restore into, so I don't particularly agree with any of the
> arguments presented above.

Right.
But increasing the difficulty of restoring a version x pg_dump with
version x + 1 is still not a thing we should lightly do.

Not that the docs currently say "it is recommended to use pg_dumpall
from the newer version". They don't say "is is not supported".

Yours,
Laurenz Albe