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pgsql: If we expect a hash join to be performed in multiple batches,

From: tgl(at)postgresql(dot)org (Tom Lane)
To: pgsql-committers(at)postgresql(dot)org
Subject: pgsql: If we expect a hash join to be performed in multiple batches,
Date: 2009-03-26 17:15:35
Message-ID: 20090326171535.6B9BF754ADE@cvs.postgresql.org (view raw or flat)
Thread:
Lists: pgsql-committerspgsql-hackers
Log Message:
-----------
If we expect a hash join to be performed in multiple batches, suppress
"physical tlist" optimization on the outer relation (ie, force a projection
step to occur in its scan).  This avoids storing useless column values when
the outer relation's tuples are written to temporary batch files.

Modified version of a patch by Michael Henderson and Ramon Lawrence.

Modified Files:
--------------
    pgsql/src/backend/nodes:
        outfuncs.c (r1.355 -> r1.356)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/nodes/outfuncs.c?r1=1.355&r2=1.356)
    pgsql/src/backend/optimizer/path:
        costsize.c (r1.205 -> r1.206)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/path/costsize.c?r1=1.205&r2=1.206)
    pgsql/src/backend/optimizer/plan:
        createplan.c (r1.256 -> r1.257)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/plan/createplan.c?r1=1.256&r2=1.257)
    pgsql/src/backend/optimizer/util:
        pathnode.c (r1.150 -> r1.151)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/util/pathnode.c?r1=1.150&r2=1.151)
    pgsql/src/include/nodes:
        relation.h (r1.170 -> r1.171)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/nodes/relation.h?r1=1.170&r2=1.171)

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