Обсуждение: pgsql: In documentaiton, clarify which commands have reduced WAL volume

In documentaiton, clarify which commands have reduced WAL volume for
wal_level = minimum.

Backpatch to 9.1 and 9.0.

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/857433b80e99e53b2187fd6a58dacaf2181fb8ce

Modified Files
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doc/src/sgml/config.sgml |   17 ++++++++++++-----
1 files changed, 12 insertions(+), 5 deletions(-)