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pgsql: Fix planning of btree index scans using ScalarArrayOpExprquals.

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: pgsql-committers(at)postgresql(dot)org
Subject: pgsql: Fix planning of btree index scans using ScalarArrayOpExprquals.
Date: 2012-09-18 16:21:14
Message-ID: E1TE0Xy-0006ts-5N@gemulon.postgresql.org (view raw or flat)
Thread:
Lists: pgsql-committers
Fix planning of btree index scans using ScalarArrayOpExpr quals.

In commit 9e8da0f75731aaa7605cf4656c21ea09e84d2eb1, I improved btree
to handle ScalarArrayOpExpr quals natively, so that constructs like
"indexedcol IN (list)" could be supported by index-only scans.  Using
such a qual results in multiple scans of the index, under-the-hood.
I went to some lengths to ensure that this still produces rows in index
order ... but I failed to recognize that if a higher-order index column
is lacking an equality constraint, rescans can produce out-of-order
data from that column.  Tweak the planner to not expect sorted output
in that case.  Per trouble report from Robert McGehee.

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/807a40c551dd30c8dd5a0b3bd82f5bbb1e7fd285

Modified Files
--------------
src/backend/optimizer/path/indxpath.c      |   15 ++++++++-
src/test/regress/expected/create_index.out |   45 ++++++++++++++++++++++++++++
src/test/regress/sql/create_index.sql      |   24 +++++++++++++++
3 files changed, 83 insertions(+), 1 deletions(-)

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Subject: pgsql: Fix array_typanalyze to work for domains over arrays.

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