Allow UNLISTEN in hot-standby mode.
Since LISTEN is (still) disallowed, UNLISTEN must be a no-op in a
hot-standby session, and so there's no harm in allowing it. This
change allows client code to not worry about whether it's connected
to a primary or standby server when performing session-state-reset
type activities. (Note that DISCARD ALL, which includes UNLISTEN,
was already allowed, making it inconsistent to reject UNLISTEN.)
Per discussion, back-patch to all supported versions.
Shay Rojansky, reviewed by Mi Tar
Discussion: https://postgr.es/m/CADT4RqCf2gA_TJtPAjnGzkC3ZiexfBZiLmA-mV66e4UyuVv8bA@mail.gmail.com
Branch
------
REL_11_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/c0aed6959541f1ce3930977c8cf8dd874308a1b5
Modified Files
--------------
doc/src/sgml/high-availability.sgml | 11 ++++++++---
src/backend/tcop/utility.c | 2 +-
src/test/regress/expected/hs_standby_allowed.out | 3 +++
src/test/regress/expected/hs_standby_disallowed.out | 4 ----
src/test/regress/sql/hs_standby_allowed.sql | 4 ++++
src/test/regress/sql/hs_standby_disallowed.sql | 2 --
6 files changed, 16 insertions(+), 10 deletions(-)