Fix some planner issues with degenerate outer join clauses. An outer join clause that didn't actually reference the RHS (perhaps only after constant-folding) could confuse the join order enforcement logic, leading to wrong query results. Also, nested occurrences of such things could trigger an Assertion that on reflection seems incorrect.
Per fuzz testing by Andreas Seltenreich. The practical use of such cases seems thin enough that it's not too surprising we've not heard field reports about it. This has been broken for a long time, so back-patch to all active branches. Branch ------ REL9_4_STABLE Details ------- http://git.postgresql.org/pg/commitdiff/e39a3b2efee07237ee34572472edf8a07dbb9e2f Modified Files -------------- src/backend/optimizer/path/joinrels.c | 26 ++++--- src/backend/optimizer/plan/initsplan.c | 18 ++++- src/test/regress/expected/join.out | 129 ++++++++++++++++++++++++++++++++ src/test/regress/sql/join.sql | 50 +++++++++++++ 4 files changed, 211 insertions(+), 12 deletions(-) -- Sent via pgsql-committers mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers
