fix sql order error

helper/statistics/order_reader.php

@@ -6,7 +6,7 @@ use function PHPUnit\Framework\isNull;
 
 class order_reader
 {
-    public function refill_vr_reader($cond,$order='order_id asc')
+    public function refill_vr_reader($cond,$order='refill_order.order_id asc')
     {
         $result = Model('')->table('refill_order,vr_order')
             ->field('min(refill_order.order_id) as min_oid,max(vr_order.order_id) as max_oid')