[CF 4564] v9 - Reducing memory consumed by RestrictInfo list translations in partitionwise join planning

This branch was automatically generated by a robot using patches from an
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https://commitfest.postgresql.org/patch/4564

The branch will be overwritten each time a new patch version is posted to
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on the master branch.

Patch(es): https://www.postgresql.org/message-id/CA+HiwqH8OaVD8LOpON=h3UyzXBwj=hHzTF_46DGvoeXzRrkx9A@mail.gmail.com
Author(s): Ashutosh Bapat

Author: Commitfest Bot

src/backend/nodes/outfuncs.c

@@ -467,7 +467,8 @@ _outEquivalenceClass(StringInfo str, const EquivalenceClass *node)
 	WRITE_OID_FIELD(ec_collation);
 	WRITE_NODE_FIELD(ec_members);
 	WRITE_NODE_FIELD(ec_sources);
-	WRITE_NODE_FIELD(ec_derives);
+	/* Only ec_derives_list is written; hash is not serialized. */
+	WRITE_NODE_FIELD(ec_derives_list);
 	WRITE_BITMAPSET_FIELD(ec_relids);
 	WRITE_BOOL_FIELD(ec_has_const);
 	WRITE_BOOL_FIELD(ec_has_volatile);

src/backend/optimizer/path/costsize.c

@@ -5848,7 +5848,8 @@ get_foreign_key_join_selectivity(PlannerInfo *root,
 				if (ec && ec->ec_has_const)
 				{
 					EquivalenceMember *em = fkinfo->fk_eclass_member[i];
-					RestrictInfo *rinfo = find_derived_clause_for_ec_member(ec,
+					RestrictInfo *rinfo = find_derived_clause_for_ec_member(root,
+																			ec,
 																			em);
 
 					if (rinfo)