pgsql: Support "x IS NOT NULL" clauses as indexscan conditions. - Mailing list pgsql-committers

Log Message:
-----------
Support "x IS NOT NULL" clauses as indexscan conditions.  This turns out
to be just a minor extension of the previous patch that made "x IS NULL"
indexable, because we can treat the IS NOT NULL condition as if it were
"x < NULL" or "x > NULL" (depending on the index's NULLS FIRST/LAST option),
just like IS NULL is treated like "x = NULL".  Aside from any possible
usefulness in its own right, this is an important improvement for
index-optimized MAX/MIN aggregates: it is now reliably possible to get
a column's min or max value cheaply, even when there are a lot of nulls
cluttering the interesting end of the index.

Modified Files:
--------------
    pgsql/doc/src/sgml:
        catalogs.sgml (r2.215 -> r2.216)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/catalogs.sgml?r1=2.215&r2=2.216)
        indexam.sgml (r2.31 -> r2.32)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/indexam.sgml?r1=2.31&r2=2.32)
        indices.sgml (r1.79 -> r1.80)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/indices.sgml?r1=1.79&r2=1.80)
    pgsql/src/backend/access/common:
        scankey.c (r1.32 -> r1.33)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/common/scankey.c?r1=1.32&r2=1.33)
    pgsql/src/backend/access/gist:
        gistget.c (r1.82 -> r1.83)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gist/gistget.c?r1=1.82&r2=1.83)
        gistscan.c (r1.76 -> r1.77)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gist/gistscan.c?r1=1.76&r2=1.77)
    pgsql/src/backend/access/nbtree:
        nbtutils.c (r1.94 -> r1.95)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/nbtree/nbtutils.c?r1=1.94&r2=1.95)
    pgsql/src/backend/executor:
        nodeIndexscan.c (r1.136 -> r1.137)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/executor/nodeIndexscan.c?r1=1.136&r2=1.137)
    pgsql/src/backend/optimizer/path:
        indxpath.c (r1.242 -> r1.243)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/path/indxpath.c?r1=1.242&r2=1.243)
    pgsql/src/backend/optimizer/plan:
        createplan.c (r1.268 -> r1.269)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/plan/createplan.c?r1=1.268&r2=1.269)
        planagg.c (r1.47 -> r1.48)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/plan/planagg.c?r1=1.47&r2=1.48)
    pgsql/src/backend/utils/adt:
        selfuncs.c (r1.264 -> r1.265)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/selfuncs.c?r1=1.264&r2=1.265)
    pgsql/src/include/access:
        skey.h (r1.37 -> r1.38)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/access/skey.h?r1=1.37&r2=1.38)
    pgsql/src/include/catalog:
        pg_am.h (r1.62 -> r1.63)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_am.h?r1=1.62&r2=1.63)
    pgsql/src/include/nodes:
        relation.h (r1.180 -> r1.181)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/nodes/relation.h?r1=1.180&r2=1.181)
    pgsql/src/include/optimizer:
        planmain.h (r1.121 -> r1.122)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/optimizer/planmain.h?r1=1.121&r2=1.122)
    pgsql/src/test/regress/expected:
        create_index.out (r1.34 -> r1.35)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/create_index.out?r1=1.34&r2=1.35)
    pgsql/src/test/regress/sql:
        create_index.sql (r1.28 -> r1.29)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/create_index.sql?r1=1.28&r2=1.29)