[pgpool-committers: 6894] pgpool: Implement automatic writing function detection by checking vola

[Tatsuo Ishii]

Implement automatic writing function detection by checking volatile property.

If a function included in SELECT/WITH has volatile property by
checking system catalog, regard it a writing function. This feature is
available only when the black_function_list and the
white_function_list are both empty. The default of the
black_function_list and the white_function_list are now empty string
so that this feature is enabled by default.

If the black_function_list or the white_function_list is not empty,
keep on existing behavior (only consult the black_function_list or the
white_function_list, not access system catalog).

Discussion: https://www.pgpool.net/pipermail/pgpool-hackers/2020-July/003730.html
Reviewed-by: Hou, Zhijie

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=b7f902d9305e0fda8ed3a8c9f098bcffae45f6b8

Modified Files
--------------
doc.ja/src/sgml/loadbalance.sgml                   |  43 +++++++-
doc/src/sgml/loadbalance.sgml                      |  43 ++++++++
src/sample/pgpool.conf.sample-logical              |   6 +-
src/sample/pgpool.conf.sample-raw                  |   6 +-
src/sample/pgpool.conf.sample-replication          |   6 +-
src/sample/pgpool.conf.sample-slony                |   6 +-
src/sample/pgpool.conf.sample-snapshot             |   6 +-
src/sample/pgpool.conf.sample-stream               |   6 +-
src/test/regression/tests/001.load_balance/test.sh |  31 ++++++
src/utils/pool_select_walker.c                     | 108 +++++++++++++++------
10 files changed, 219 insertions(+), 42 deletions(-)