diff --git a/src/backend/executor/nodeMemoize.c b/src/backend/executor/nodeMemoize.c
index 8f79a23284..93ca5057e1 100644
--- a/src/backend/executor/nodeMemoize.c
+++ b/src/backend/executor/nodeMemoize.c
@@ -161,6 +161,10 @@ MemoizeHash_hash(struct memoize_hash *tb, const MemoizeKey *key)
 	TupleTableSlot *pslot = mstate->probeslot;
 	uint32		hashkey = 0;
 	int			numkeys = mstate->nkeys;
+	ExprContext *econtext = mstate->ss.ps.ps_ExprContext;
+	MemoryContext oldcontext;
+
+	oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
 
 	if (mstate->binary_mode)
 	{
@@ -203,6 +207,7 @@ MemoizeHash_hash(struct memoize_hash *tb, const MemoizeKey *key)
 		}
 	}
 
+	MemoryContextSwitchTo(oldcontext);
 	return murmurhash32(hashkey);
 }