Dave Cramer <davecra...@gmail.com> writes: > On Fri, 5 Apr 2024 at 12:09, Jelte Fennema-Nio <m...@jeltef.nl> wrote: >> Setting PGC_PROTOCOL gucs would be allowed in the startup packet, >> which is fine afaict because that's also something that's part of the >> protocol level and is thus fully controlled by client libraries and >> poolers) But other than that: Yes, conf files, ALTER, and SET cannot >> change these GUCs.
> +1 I don't buy that argument, actually. libpq, and pretty much every other client AFAIK, has provisions to let higher code levels insert random options into the startup packet. So to make this work libpq would have to filter or at least inspect such options, which is logic that doesn't exist and doesn't seem nice to need. The other problem with adding these things in the startup packet is that when you send that packet, you don't know what the server version is and hence don't know if it will take these options. What's so bad about insisting that these options must be sent in a separate message? regards, tom lane