mysql 触发器抛出异常处理

DELIMITER $$

CREATE TRIGGER `before_employee_update` BEFORE UPDATE ON `employees`
FOR EACH ROW
BEGIN
    IF NEW.salary < 0 THEN
        SIGNAL SQLSTATE '45000'
        SET MESSAGE_TEXT = 'Salary cannot be negative';
    END IF;
END$$

DELIMITER ;

DELIMITER $$

CREATE PROCEDURE `check_salary`(IN `salary` DECIMAL(10, 2))
BEGIN
    IF salary < 0 THEN
        SIGNAL SQLSTATE '45000'
        SET MESSAGE_TEXT = 'Salary cannot be negative';
    END IF;
END$$

CREATE TRIGGER `before_employee_update` BEFORE UPDATE ON `employees`
FOR EACH ROW
BEGIN
    CALL check_salary(NEW.salary);
END$$

DELIMITER ;

DELIMITER $$

CREATE TRIGGER `before_employee_update` BEFORE UPDATE ON `employees`
FOR EACH ROW
BEGIN
    IF NEW.salary < 0 THEN
        LEAVE before_employee_update;
    END IF;
END$$

DELIMITER ;