From 7de878f0ca34d37458509e331f92ed3eb8598892 Mon Sep 17 00:00:00 2001
From: Marco Slot <marco.slot@gmail.com>
Date: Tue, 1 Mar 2022 19:08:12 +0100
Subject: [PATCH] Fix some bugs

---
 .../utils/extract_equality_filters_from_query.c          | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/backend/distributed/utils/extract_equality_filters_from_query.c b/src/backend/distributed/utils/extract_equality_filters_from_query.c
index 45bfb262e..c6657f8fb 100644
--- a/src/backend/distributed/utils/extract_equality_filters_from_query.c
+++ b/src/backend/distributed/utils/extract_equality_filters_from_query.c
@@ -89,6 +89,7 @@ extract_equality_filters_from_query(PG_FUNCTION_ARGS)
 	char *queryString = text_to_cstring(PG_GETARG_TEXT_P(0));
 
 	MemoryContext oldContext = CurrentMemoryContext;
+	ResourceOwner oldOwner = CurrentResourceOwner;
 
 	/* capture filters via hooks */
 	PlannerRestrictionContext *plannerRestrictionContext =
@@ -153,6 +154,12 @@ extract_equality_filters_from_query(PG_FUNCTION_ARGS)
 				Var *leftVar = NULL;
 				Const *rightConst = NULL;
 
+				if (!NodeIsEqualsOpExpr((Node *) clause))
+				{
+					/* not an equals expression */
+					continue;
+				}
+
 				if (!VarConstOpExprClause((OpExpr *) clause, &leftVar, &rightConst) &&
 					!VarNullWrapperOpExprClause(clause, wrapperFunctionId, &leftVar))
 				{
@@ -273,6 +280,8 @@ extract_equality_filters_from_query(PG_FUNCTION_ARGS)
 
 		FlushErrorState();
 		RollbackAndReleaseCurrentSubTransaction();
+		MemoryContextSwitchTo(oldContext);
+		CurrentResourceOwner = oldOwner;
 	}
 	PG_END_TRY();