系统变量"MESSAGE_TEXT"在MySQL中不能使用SIGNAL语句?

问题描述

我的代码是:我正在使用mysql 5.6和workbench 6.3CE

My code is:i am using mysql 5.6 and workbench 6.3CE

 CREATE DEFINER=`root`@`windows7test-pc` PROCEDURE `p`(divisor INT)
 BEGIN
 Declare MESSAGE_TEXT varchar(200);
 IF divisor = 0 THEN
 BEGIN
  DECLARE my_error CONDITION FOR SQLSTATE '45000';
  SIGNAL my_error;
  set MESSAGE_TEXT='error occured in if block';
 END;
 END IF;

 END

当我应用此存储过程时，我没有收到任何错误，但是当我通过调用 call p(0)语句运行此存储库时，我仅收到系统错误消息，该错误消息为错误代码:1644 未处理的用户定义的异常情况.但是我的问题是，为什么mysql服务器未生成我的错误消息，是 MESSAGE_TEXT ='if块中发生了错误'; ?

when i apply this stored procedure then i get no error but when i run this by calling call p(0) statement then i get only system error message which is Error Code: 1644 Unhandled user-defined exception condition.but my question is that why the mysql server not generate my error message whic is MESSAGE_TEXT='error occured in if block'; ?

推荐答案

您没有将message_text声明为变量.

You do not declare message_text as a variable.

您不DECLARE ... CONDITION.

您必须在与SIGNAL相同的语句中包含SET的值.

You do have to include the values to SET in the same statement as SIGNAL.

语法很简单:

IF divisor = 0 THEN
  SIGNAL SQLSTATE '45000' SET message_text = 'division: ur doing it wrong';
END IF;

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