[pgpool-committers: 10172] pgpool: Optimize query cache invalidation for ALTER ROLE.

[Tatsuo Ishii]

Optimize query cache invalidation for ALTER ROLE.

Commit 6b7d585eb1c693e4ffb5b8e6ed9aa0f067fa1b89 invalidates query
cache if any ALTER ROLE/USER statement is used. Actually this is an
overkill. Because following queries do not affect the privilege of the
role.

- ALTER ROLE user WITH [ENCRYPTED] PASSWORD
- ALTER ROLE user WITH CONNECTION LIMIT

So do not invalidate query cache if those commands are used.

Backpatch-through: v4.1
Discussion: https://www.pgpool.net/pipermail/pgpool-hackers/2024-October/004532.html

Branch
------
V4_2_STABLE

Details
-------
https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=273901f146ab9d3b1903f1b213ea2c10182a3363

Modified Files
--------------
doc.ja/src/sgml/memcache.sgml                      |  2 +-
doc/src/sgml/memcache.sgml                         |  2 +-
src/protocol/CommandComplete.c                     | 36 +++++++++++++++++++++-
src/test/regression/tests/006.memqcache/expected.n | 29 +++++++++++++++++
src/test/regression/tests/006.memqcache/expected.r | 31 +++++++++++++++++++
src/test/regression/tests/006.memqcache/expected.s | 29 +++++++++++++++++
src/test/regression/tests/006.memqcache/test.sh    | 12 ++++++++
7 files changed, 138 insertions(+), 3 deletions(-)