Обсуждение: pgsql: Add a few paragraphs to B-tree README explaining L&Y algorithm.

Add a few paragraphs to B-tree README explaining L&Y algorithm.

This gives an overview of what Lehman & Yao's paper is all about, so that
you can understand the rest of the README without having to read the paper.

Per discussion with Peter Geoghegan and others.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/49b86fb1c97878ea2e3a8118df072c95f60077ac

Modified Files
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src/backend/access/nbtree/README |   21 +++++++++++++++++++--
1 file changed, 19 insertions(+), 2 deletions(-)