Fix documentation error in commit 8703059c6b.

Etsuro Fujita spotted a thinko in the README commentary.
This commit is contained in:
Tom Lane 2015-10-01 10:31:22 -04:00
parent 3123ee0db2
commit 21995d3f6d
1 changed files with 1 additions and 1 deletions

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@ -254,7 +254,7 @@ lower leftjoin has min LHS of {B} and min RHS of {C,D}. Given such
information, join_is_legal would think it's okay to associate the upper
join into the lower join's RHS, transforming the query to
B leftjoin (A leftjoin (C innerjoin D) on Pa) on (Pbcd)
which yields totally wrong answers. We prevent that by forcing the min LHS
which yields totally wrong answers. We prevent that by forcing the min RHS
for the upper join to include B. This is perhaps overly restrictive, but
such cases don't arise often so it's not clear that it's worth developing a
more complicated system.