Log Message:
-----------
Fix longstanding bug that would sometimes let the planner generate a bad plan
for an outer join; symptom is bogus error "RIGHT JOIN is only supported with
merge-joinable join conditions". Problem was that select_mergejoin_clauses
did its tests in the wrong order. We need to force left join not right join
for a merge join when there are non-mergeable join clauses; but the test for
this only accounted for mergejoinability of the clause operator, and not
whether the left and right Vars were of the proper relations. Per report
from Jean-Pierre Pelletier.
Tags:
----
REL7_3_STABLE
Modified Files:
--------------
pgsql/src/backend/optimizer/path:
joinpath.c (r1.71.2.1 -> r1.71.2.2)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/path/joinpath.c.diff?r1=1.71.2.1&r2=1.71.2.2)