Re: correction suggestion for https://www.postgresql.org/docs/17/auth-username-maps.html

"David G. Johnston" <david(dot)g(dot)johnston(at)gmail(dot)com> writes:
> Its good as far a narrow fix goes.

> But how about the attached? More invasive but covers the salient points
> better, IMO, and less repetitive than having the two fields have their own
> basically copy-pasted paragraphs.

Meh... I initially thought that merging the two paras sounded like a
good idea, but I'm not finding that this formulation reads any better.
Notably, as things stand we have parallel constructions
"If the <field> starts with an <x> character" in the preceding para as
well as these two, and I think it's good to keep that parallelism.
I do agree that it's overly repetitive, but we could improve that by
dropping the second instance of the parenthetical link to
posix-syntax-details.

> I didn't add an example but felt the point "be referenced a single time
> within" to be needed since, usefulness not withstanding, writing \1\1 for
> database-username works but only the first instance of \1 is replaced.

Hmm, I wonder if that isn't a bug we should fix. It's hard to believe
anyone is relying on the second \1 *not* getting replaced, and perhaps
there are use-cases for multiple replacements.

> Also, should we attempt to align this documentation and
> pg_ident.conf.sample as pertains to pg-username vs. database-username?

Agreed that making pg_ident.conf.sample match would be an improvement.

regards, tom lane