Names of run-time configuration parameters (was: Limiting the operations that client-side code can perform upon its database backend's artifacts)

On 2022-09-30 17:59:01 -0700, Bryn Llewellyn wrote:
> set rls.tenant_id=42;

This works because there is a "." in the name. Without the "."
PostgreSQL complains:

hjp=> set rls_tenant_id=42;
ERROR:  unrecognized configuration parameter "rls_tenant_id"


I think I sort of knew this but had forgotten about it, so checked the
manual for the exact rules. Unfortunately I couldn't find them (I
checked https://www.postgresql.org/docs/14/sql-set.html,
https://www.postgresql.org/docs/14/config-setting.html,
https://www.postgresql.org/docs/14/functions-admin.html#FUNCTIONS-ADMIN-SET,
and browser the table of content and the index).

From the documentation I get the impression that you can only set
existing parameters, not your own.

I therefore suggest adding something like this to the section
"configuration_parameter" in
https://www.postgresql.org/docs/14/sql-set.html:

| In addition, any name including a single dot (".") can be set. This
| allows an application to define its own run-time parameters. Using the
| application name as a prefix reduces the probability of name conflicts
| with other applications or extensions.

(This of course assumes that the behaviour is intentional and not a
bug.)

        hp

--
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp@hjp.at         |    -- Charles Stross, "Creative writing
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