Обсуждение: pgsql: Doc: minor clarifications in xindex.sgml.

Doc: minor clarifications in xindex.sgml.

I noticed some slightly confusing or out-of-date verbiage here
while working on the window RANGE patch.  Seems worth committing
separately.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/64fb645914741ffc3aee646308416c209c6ff06b

Modified Files
--------------
doc/src/sgml/xindex.sgml | 34 ++++++++++++++++++++++++----------
1 file changed, 24 insertions(+), 10 deletions(-)