首页 > 解决方案 > 引发错误在 MySQL 触发器中不起作用

问题描述

如果一个人的 lastname 不是全大写或者他们的 firstname 的第一个字母不是 caps ,我试图在我的触发器中引发一个错误。但是,如果遇到这些情况,我的代码似乎不会发出警报。有人可以向我解释我该怎么做吗?

这是我的桌子:

DROP TABLE IF EXISTS people;
CREATE TABLE IF NOT EXISTS people (
Id_People smallint(5) unsigned NOT NULL AUTO_INCREMENT,
Firstname varchar(20) NOT NULL,
Lastname varchar(20) NOT NULL,
Birth     DATE,
PRIMARY KEY (Id_People)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8 AUTO_INCREMENT=1002 ;DROP TRIGGER IF EXISTS insert_people;

这是我的触发器

DROP TRIGGER IF EXISTS insert_people;
DELIMITER $$
CREATE TRIGGER insert_people BEFORE INSERT ON people
FOR EACH ROW BEGIN 
    IF NOT  (NEW.Lastname like UCASE ) THEN 
          SIGNAL SQLSTATE '45000'
            SET MESSAGE_TEXT = 'the lastname must be in full caps ';
           
    ELSE IF
         NOT (NEW.Firstname like ucfirst ) THEN
           SIGNAL SQLSTATE '45000'
            SET MESSAGE_TEXT = 'the first letter of the firstname must be in caps'; 
    
     END IF; 
  END IF;
 
END$$

标签: mysqltriggersraiseerror

解决方案


你的代码发现那些是不正确的。

请添加DELIMITER到触发代码,因为在示例站点中不需要

DROP TABLE IF EXISTS people;
CREATE TABLE IF NOT EXISTS people (
Id_People smallint(5) unsigned NOT NULL AUTO_INCREMENT,
Firstname varchar(20) NOT NULL,
Lastname varchar(20) NOT NULL,
Birth     DATE,
PRIMARY KEY (Id_People)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8 AUTO_INCREMENT=1002 ;DROP TRIGGER IF EXISTS insert_people;
CREATE TRIGGER insert_people BEFORE INSERT ON people
FOR EACH ROW BEGIN 
    IF NOT  (NEW.Lastname=BINARY UPPER(NEW.Lastname)) THEN 
          SIGNAL SQLSTATE '45000'
            SET MESSAGE_TEXT = 'the lastname must be in full caps ';
           
    ELSE IF
         NOT (ASCII(NEW.Firstname) BETWEEN 65 AND 90 ) THEN
           SIGNAL SQLSTATE '45000'
            SET MESSAGE_TEXT = 'the first letter of the firstname must be in caps'; 
    
     END IF; 
  END IF;
 
END
INSERT INTO people VALUES (NULL,'Hallo','Kitty','1980-01-01')
姓氏必须大写 
INSERT INTO people VALUES (NULL,'hallo','KITTY','1980-01-01')
名字的第一个字母必须大写

db<>在这里摆弄


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