Re: Add primary keys to system catalogs

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Joel Jacobson" <joel@compiler.org>
Cc: "Peter Eisentraut" <peter.eisentraut@2ndquadrant.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2021-01-22T15:42:33Z
Lists: pgsql-hackers
"Joel Jacobson" <joel@compiler.org> writes:
> I ran this query (on a patched database) to see if there are still any catalog tables without primary keys:
> ...
> pg_depend
> pg_shdepend

Yeah, this is noted in the patch's own regression tests.

> Wouldn't it be possible to add primary keys to these two as well?

Neither of the existing indexes is suitable, not being unique.

We could imagine adding a unique index across the whole column set,
but that would be an awfully large price to pay for neatnik-ism.
Also, at least for pg_depend (less sure about pg_shdepend), some code
cleanup would be required, because I don't think that we try very
hard to avoid making duplicate dependency entries.  On the whole
I feel this'd be counterproductive.

			regards, tom lane



Commits

  1. Add primary keys and unique constraints to system catalogs