Re: [PATCH] Fix null pointer dereference in PG19
Tom Lane <tgl@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Paul A Jungwirth <pj@illuminatedcomputing.com>
Cc: Peter Eisentraut <peter@eisentraut.org>,
Aleksander Alekseev <aleksander@tigerdata.com>,
PostgreSQL Development <pgsql-hackers@postgresql.org>
Date: 2026-07-08T02:07:37Z
Lists: pgsql-hackers
Paul A Jungwirth <pj@illuminatedcomputing.com> writes: > On Tue, Apr 21, 2026 at 8:24 AM Tom Lane <tgl@sss.pgh.pa.us> wrote: >> Checking this at parse time is completely the wrong thing. >> The view could have gained (or lost) triggers by the time >> it's executed. > But INSTEAD OF triggers are selected in the rewriter, which uses the > same relcache snapshot as parse analysis. And a concurrent change > can't sneak in different triggers, because that causes a relcache > invalidation, so we redo the parse & rewrite phases. You have forgotten about views and rewrite rules. Those go to disk in post-parser form, and will be rewritten only at execution sometime later, *without* a re-parse. regards, tom lane