From: David Rowley Date: Thu, 10 Apr 2025 05:33:58 +0000 (+1200) Subject: Update wording in optimizer/README for EquivalenceClasses X-Git-Tag: REL_18_BETA1~181 X-Git-Url: http://git.postgresql.org/gitweb/?a=commitdiff_plain;h=d7c04db27aeba1718d8059eae9a6e6a5eedc01b8;p=postgresql.git Update wording in optimizer/README for EquivalenceClasses d69d45a5a changed how em_is_child members are stored in EquivalenceClasses. Children are no longer stored in the ec_members list. optimizer/README mentioned that most operations "should ignore child members", but that felt a little untrue now since child members are now stored in a separate place, they simply won't be found by the normal means of looking (a foreach loop over ec_members), and if you don't find them, there's technically no need to "ignore" them. Here we tweak the wording slightly to reflect the new storage location for child members. Reported-by: Amit Langote Author: Amit Langote Author: David Rowley Discussion: https://postgr.es/m/CA+HiwqE8v=EuAP_3F_A2xn8zWx+nG_etW_Fe_DvKO-Fkx=+DdQ@mail.gmail.com --- diff --git a/src/backend/optimizer/README b/src/backend/optimizer/README index 21c2db5a85c..9c724ccfabf 100644 --- a/src/backend/optimizer/README +++ b/src/backend/optimizer/README @@ -902,7 +902,7 @@ contain the equivalent child-relation variables or expressions. These members are *not* full-fledged members of the EquivalenceClass and do not affect the class's overall properties at all. They are kept only to simplify matching of child-relation expressions to EquivalenceClasses. -Most operations on EquivalenceClasses should ignore child members. +Most operations on EquivalenceClasses needn't look at child members. PathKeys