Обсуждение: pgsql-server/ oc/src/sgml/perform.sgml oc/src/ ...

Поиск
Список
Период
Сортировка

pgsql-server/ oc/src/sgml/perform.sgml oc/src/ ...

От
tgl@postgresql.org (Tom Lane)
Дата:
CVSROOT:    /cvsroot
Module name:    pgsql-server
Changes by:    tgl@postgresql.org    03/01/25 18:10:30

Modified files:
    doc/src/sgml   : perform.sgml release.sgml runtime.sgml
    src/backend/optimizer/path: allpaths.c
    src/backend/optimizer/plan: planner.c
    src/backend/optimizer/prep: prepjointree.c
    src/backend/utils/misc: guc.c postgresql.conf.sample
    src/bin/psql   : tab-complete.c
    src/include/optimizer: paths.h prep.h
    src/test/regress/expected: join.out

Log message:
    Allow the planner to collapse explicit inner JOINs together, rather than
    necessarily following the JOIN syntax to develop the query plan.  The old
    behavior is still available by setting GUC variable JOIN_COLLAPSE_LIMIT
    to 1.  Also create a GUC variable FROM_COLLAPSE_LIMIT to control the
    similar decision about when to collapse sub-SELECT lists into their parent
    lists.  (This behavior existed already, but the limit was always
    GEQO_THRESHOLD/2; now it's separately adjustable.)