Thread: pgsql/ rc/include/utils/lsyscache.h rc/backend ...

pgsql/ rc/include/utils/lsyscache.h rc/backend ...

From
Tom Lane
Date:
CVSROOT:    /home/projects/pgsql/cvsroot
Module name:    pgsql
Changes by:    tgl@hub.org    01/05/08 20:35:09

Modified files:
    src/include/utils: lsyscache.h
    src/backend/utils/cache: lsyscache.c
    src/backend/optimizer/path: costsize.c
    doc/src/sgml   : perform.sgml

Log message:
    Cause planner to make use of average-column-width statistic that is now
    collected by ANALYZE.  Also, add some modest amount of intelligence to
    guesses that are used for varlena columns in the absence of any ANALYZE
    statistics.  The 'width' reported by EXPLAIN is finally something less
    than totally bogus for varlena columns ... and, in consequence, hashjoin
    estimating should be a little better ...