查询订单是否是第一次下单

business/jxcallback/orderman/orderman_ext.go

@@ -1374,7 +1374,7 @@ func GetOrderUserBuyFirst(ctx *jxcontext.Context, vendorOrderID string) (orderPa
 		  FROM goods_order a, order_pay b 
 		 WHERE a.vendor_order_id = b.vendor_order_id 
 		   AND a.vendor_id = b.vendor_id
-		   AND b.pay_finished_at <> ''
+		   AND b.pay_finished_at <> NULL
 		   AND a.vendor_order_id = ?
 	`
 	sqlParams := []interface{}{vendorOrderID}