Question

USE brendasdms;

DROP TRIGGER IF EXISTS  Customers_Before_Insert; 

DELIMITER //

        CREATE TRIGGER Customers_Before_Insert
        BEFORE INSERT ON Customers
        FOR EACH ROW 
        
      BEGIN 
		 IF(NEW.Email NOT LIKE '%_@%_.__%') THEN 
				 SIGNAL SQLSTATE VALUE '45000'
				  SET MESSAGE_TEXT= 'The email column doesn\'t contain @ symbol or .(dot) domain'; 
           END IF ; 

           IF (NEW.Phone NOT REGEXP '[0-9]{3}-[0-9]{3}-[0-9]{4}') THEN
                   SIGNAL SQLSTATE VALUE '45000'
				  SET MESSAGE_TEXT= 'The Phone Number Needs to be at least 10 digits long';
		END IF ; 

      END; //

DELIMITER ;



INSERT INTO Customers(FirstName, LastName, Email, Phone) 
              VALUES('Caroline', 'Wright', 'CarolineWrightrocketmail.com', '330-333-3448'); 
              
		
SELECT 
Customers.LastName, 
Customers.FirstName, 
Customers.Email 
 FROM  Customers
 WHERE Customer_ID= last_insert_id();

大家好。

我试图找出可以同时在触发器内执行两个if语句，以便在输出窗口中一个接一个地显示这两个错误消息。我可以使用for循环或while循环来完成此任务。任何建议都会很棒。这是我上面附带的代码。

Answer 1

您可以在发信号之前将消息连接在一起：

CREATE TRIGGER Customers_Before_Insert
    BEFORE INSERT ON Customers
    FOR EACH ROW 
BEGIN
    DECLARE v_msg varchar(255) DEFAULT '';

    IF (NEW.Email NOT LIKE '%_@%_.__%') THEN 
        set v_msg = 'The email column doesn''t contain @ symbol or .(dot) domain';
    END IF;
    IF (NEW.Phone NOT REGEXP '[0-9]{3}-[0-9]{3}-[0-9]{4}') THEN
        set v_msg = concat_ws('\n', v_msg, 'The Phone Number Needs to be at least 10 digits long');
    END IF;

    IF v_msg <> '' THEN
        SIGNAL SQLSTATE VALUE '45000' SET MESSAGE_TEXT = v_msg;
    END IF ; 
END; //

您不能在一个触发器中发出两次信号，因为信号结束了处理。因此，构建您想要构建的消息。

如何在输出窗口中同时在触发器内执行两个if语句？

1 个答案: