diff --git a/src/backend/partitioning/partprune.c b/src/backend/partitioning/partprune.c
index 58ec2a6..f02bd30 100644
--- a/src/backend/partitioning/partprune.c
+++ b/src/backend/partitioning/partprune.c
@@ -2705,6 +2705,9 @@ pull_partkey_params(PartitionPruneInfo *pinfo, List *steps)
 		{
 			Expr	   *expr = lfirst(lc2);
 
+			if (contain_volatile_functions((Node *) expr))
+				continue;
+
 			if (IsA(expr, Param))
 			{
 				Param	   *param = (Param *) expr;
@@ -2727,6 +2730,13 @@ pull_partkey_params(PartitionPruneInfo *pinfo, List *steps)
 				}
 				gotone = true;
 			}
+			else if (!IsA(expr, Const))
+			{
+				Param	*param = (Param *) expr;
+				pinfo->execparams = bms_add_member(pinfo->execparams,
+												   param->paramid);
+				gotone = true;
+			}
 		}
 	}
 
@@ -3031,37 +3041,35 @@ static bool
 partkey_datum_from_expr(PartitionPruneContext *context,
 						Expr *expr, int stateidx, Datum *value)
 {
-	switch (nodeTag(expr))
-	{
-		case T_Const:
-			*value = ((Const *) expr)->constvalue;
-			return true;
-
-		case T_Param:
-
-			/*
-			 * When being called from the executor we may be able to evaluate
-			 * the Param's value.
-			 */
-			if (context->planstate &&
-				bms_is_member(((Param *) expr)->paramid, context->safeparams))
-			{
-				ExprState  *exprstate;
-				ExprContext *ectx;
-				bool		isNull;
+	if (contain_volatile_functions((Node *) expr))
+		return false;
 
-				exprstate = context->exprstates[stateidx];
-				ectx = context->planstate->ps_ExprContext;
-				*value = ExecEvalExprSwitchContext(exprstate, ectx, &isNull);
-				if (isNull)
-					return false;
+	if (IsA(expr, Const))
+	{
+		*value = ((Const *) expr)->constvalue;
+		return true;
+	}
+	else
+	{
+		/*
+		 * When being called from the executor we may be able to evaluate
+		 * the Param's value.
+		 */
+		if (context->planstate &&
+			bms_is_member(((Param *) expr)->paramid, context->safeparams))
+		{
+			ExprState  *exprstate;
+			ExprContext *ectx;
+			bool		isNull;
 
-				return true;
-			}
-			break;
+			exprstate = context->exprstates[stateidx];
+			ectx = context->planstate->ps_ExprContext;
+			*value = ExecEvalExprSwitchContext(exprstate, ectx, &isNull);
+			if (isNull)
+				return false;
 
-		default:
-			break;
+			return true;
+		}
 	}
 
 	return false;