[pgpool-committers: 8717] pgpool: Fix to not cache SELECT having functions with return types are

[Tatsuo Ishii]

Fix to not cache SELECT having functions with return types are timestamptz or timetz.

Functions with return type is timestamptz or timetz is affected by time zone setting.
Consider following scenario:

1) SELECT having such functions gets called and cache created.

2) time zone is changed.

3) same SELECT is called and the cache is used. The cache value is
correct any more because of the time zone change.

Discussion: https://www.pgpool.net/pipermail/pgpool-general/2022-July/008367.html

Branch
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V4_2_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=da33d44b8cd86c736c3fdaa9f5a26766056f37ce

Modified Files
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src/test/regression/tests/006.memqcache/test.sh |   3 +
src/utils/pool_select_walker.c                  | 113 ++++++++++++++++++++++--
2 files changed, 108 insertions(+), 8 deletions(-)