[pgpool-committers: 10442] pgpool: Fix long standing bind bug with query cache.

[Tatsuo Ishii]

Fix long standing bind bug with query cache.

When a named statement is prepared, it is possible to bind then
execute without a parse message. Problem is, table oids which are
necessary to invalidate query cache at execute or COMMIT was collected
only in parse messages process (Parse()). Thus if bind is executed
without parse after previous execute, no table oids were collected,
and pgpool failed to invalidate query cache.

Fix is collecting table oids at bind time too.

Add regression test to 006.memqcache.

Problem reported by and test program provided by Achilleas Mantzios
<a.mantzios at cloud.gatewaynet.com>.

Discussion: [pgpool-general: 9427] Clarification on query results cache visibility
https://www.pgpool.net/pipermail/pgpool-general/2025-April/009430.html

Backpatch-through: v4.2

Branch
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V4_2_STABLE

Details
-------
https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=14d3789805d22fccabcc3b9fd6ac35a3c35a6ebd

Modified Files
--------------
src/protocol/pool_proto_modules.c                  | 27 +++++++++++
src/test/regression/tests/006.memqcache/expected.6 | 38 +++++++++++++++
src/test/regression/tests/006.memqcache/expected.7 | 54 ++++++++++++++++++++++
.../tests/006.memqcache/query_cache_bug6.data      | 38 +++++++++++++++
.../tests/006.memqcache/query_cache_bug7.data      | 52 +++++++++++++++++++++
src/test/regression/tests/006.memqcache/test.sh    |  7 ++-
6 files changed, 215 insertions(+), 1 deletion(-)