From f458c90bff45ecae91fb55ef2b938af37d977af3 Mon Sep 17 00:00:00 2001
From: Bruce Momjian <bruce@momjian.us>
Date: Mon, 5 Sep 2011 22:08:14 -0400
Subject: [PATCH] Add C comment about why we send cache invalidation messages
 for session-local objects.

---
 src/backend/utils/cache/inval.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/backend/utils/cache/inval.c b/src/backend/utils/cache/inval.c
index 337fe64e10c..98dc3adf30c 100644
--- a/src/backend/utils/cache/inval.c
+++ b/src/backend/utils/cache/inval.c
@@ -812,6 +812,10 @@ ProcessCommittedInvalidationMessages(SharedInvalidationMessage *msgs,
  * about CurrentCmdInvalidMsgs too, since those changes haven't touched
  * the caches yet.
  *
+ * We still send invalidation messages for session-local objects to other
+ * backends because, while other backends cannot see any tuples, they can
+ * drop tables that are session-local to another session.
+ * 
  * In any case, reset the various lists to empty.  We need not physically
  * free memory here, since TopTransactionContext is about to be emptied
  * anyway.
-- 
GitLab