Horton

Re: Clarification on Role Access Rights to Table Indexes

Ayush Vatsa <ayushvatsa1810@gmail.com>

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From: Ayush Vatsa <ayushvatsa1810@gmail.com>
To: Nathan Bossart <nathandbossart@gmail.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, "David G. Johnston" <david.g.johnston@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2025-03-08T15:04:40Z
Lists: pgsql-hackers, pgsql-general 
> I'm wondering whether setting missing_ok to true is correct here.  IIUC we
> should have an AccessShareLock on the index, but I don't know if that's
> enough protection.

Since we are already opening the relation with rel = relation_open(relOid,
AccessShareLock);,
if relOid does not exist, it will throw an error. If it does exist, we
acquire an AccessShareLock,
preventing it from being dropped.

By the time we reach IndexGetRelation(), we can be confident that relOid
exists and is
protected by the lock. Given this, it makes sense to keep missing_ok = false
here.

Let me know if you agree or if you see any scenario where
missing_ok = true would be preferable—I can update the condition
accordingly.

Thanks!
Ayush Vatsa
SDE AWS

Commits

  1. Fix privilege checks for pg_prewarm() on indexes.

  2. Fix lookup code for REINDEX INDEX.

  3. Fix redefinition of typedef RangeVar.

  4. Fix lookups in pg_{clear,restore}_{attribute,relation}_stats().

  5. dblink: Avoid locking relation before privilege check.