From: Tom Lane <tgl@sss.pgh.pa.us>
To: imchifan@163.com
cc: Peter Eisentraut <peter@eisentraut.org>, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #19703: information_schema.usage_privileges omits a sequence
 owner's implicit USAGE privilege
In-reply-to: <19703-49d6f1796001a6d7@postgresql.org>
References: <19703-49d6f1796001a6d7@postgresql.org>
Comments: In-reply-to PG Bug reporting form <noreply@postgresql.org>
	message dated "Sat, 19 Sep 2026 13:44:36 -0000"
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Date: Sun, 20 Sep 2026 11:49:45 -0400
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PG Bug reporting form <noreply@postgresql.org> writes:
> For a newly created sequence, has_sequence_privilege reports that the ow=
ner
> has USAGE, but information_schema.usage_privileges omits that privilege.=
 The
> view reports the owner privilege only after the same USAGE privilege is
> redundantly granted explicitly.

I think the problem is that the "sequences" arm of usage_privileges
writes

            SELECT oid, relname, relnamespace, relkind, relowner, (aclexpl=
ode(coalesce(relacl, acldefault('r', relowner)))).* FROM pg_class

but the acldefault code for sequences is 's' not 'r', so the wrong
set of default ACL bits is injected.  We would see a bunch of
obviously-inapplicable privileges reported, except that the query
then applies a filter:

          AND c.prtype IN ('USAGE')

and we end up reporting nothing.

This appears to go clear back to 82e83f46a.

			regards, tom lane