如果第一次更新成功执行，则执行第二次更新

本文介绍了如果第一次更新成功执行，则执行第二次更新的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

存储过程

CREATE DEFINER=`root`@`localhost` PROCEDURE `Sample`(IN itemId INT, IN itemQnty DOUBLE, IN invID INT) BEGIN DECLARE crntQnty DOUBLE; DECLARE nwQnty DOUBLE; SET crntQnty=(SELECT `QuantityOnHand` FROM `item` WHERE id=itemId); SET nwQnty=itemQnty+crntQnty; UPDATE `item` SET `QuantityOnHand`=nwQnty WHERE `Id`=itemId; UPDATE `inventoryentry` SET `Status` = 1 WHERE `InventoryID`=invID AND `ItemID`=itemId; END$$

在此存储过程中，我有两个更新语句.如果第一次更新成功执行，然后第二次执行.需要进行哪些更改?

In this stored procedure I have two update statements. IF first update execute successfully then second execute. what changes required to be made?

推荐答案

在第一个UPDATE之后，您可以检查受ROW_COUNT()影响的行数.

After the first UPDATE you can check the number of rows that were affected by ROW_COUNT().

如果ROW_COUNT()返回所需的更新数量(也许> 0)，则仅触发第二个UPDATE.

If the ROW_COUNT() returns the desired number of updates you want (maybe > 0) then only fire second UPDATE.

Yo可以用IF - END IF包围第二个UPDATE，检查受影响的行数.

Yo can surround the second UPDATE by an IF - END IF checking for the number of rows that were affected.