diff --git a/sql/bcnftdb.sql b/sql/bcnftdb.sql
index d41766f6..903c3222 100644
--- a/sql/bcnftdb.sql
+++ b/sql/bcnftdb.sql
@@ -192,7 +192,7 @@ CREATE TABLE `t_sale` (
   `createtime` int(11) NOT NULL DEFAULT '0' COMMENT '创建时间',
   `modifytime` int(11) NOT NULL DEFAULT '0' COMMENT '修改时间',
   PRIMARY KEY (`idx`),
-  KEY `idx_order_id` (`order_id`),
+  UNIQUE KEY `idx_order_id` (`order_id`),
   KEY `idx_buyer` (`buyer`),
   KEY `idx_seller` (`seller`)
 ) ENGINE=InnoDB AUTO_INCREMENT=10001 DEFAULT CHARSET=utf8 COLLATE=utf8_bin;