Обсуждение: pgsql: Doc updates for index-only scans.

Doc updates for index-only scans.

Document that routine vacuuming is now also important for the purpose
of index-only scans; and mention in the section that describes the
visibility map that it is used to implement index-only scans.

Marti Raudsepp, with some changes by me.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/5b9c1e6d52dfd022a074462e029bfd7f7bc4321c

Modified Files
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doc/src/sgml/maintenance.sgml |   32 ++++++++++++++++++++++++++++++++
doc/src/sgml/storage.sgml     |   15 ++++++++++-----
2 files changed, 42 insertions(+), 5 deletions(-)