[pgpool-committers: 7604] pgpool: Doc: enhance show pool_cache manual.

[Tatsuo Ishii]

Doc: enhance show pool_cache manual.

Add note that not all columns shows meaningful values when cache
storage is memcached.

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=e9aadade1ea8dc91a3fa1238b4acf51a94f2a866

Modified Files
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doc.ja/src/sgml/ref/show_pool_cache.sgml | 12 ++++++++++++
doc/src/sgml/ref/show_pool_cache.sgml    |  8 ++++++++
2 files changed, 20 insertions(+)