mysql - 在 MYSQL 中创建 BEFORE INSERT 触发器

Question

我需要帮助在 mySQL Bench 上创建 BEFORE INSERT TRIGGER。我是新手，请。

CREATE TABLE `quincyninying`.`toytracking` (
`Toyid` INT NOT NULL,
`ToyName` VARCHAR(50) NULL,
`Toycost` DECIMAL NULL,
`ToyAction` VARCHAR(50) NULL,
`ActionDate` DATETIME NULL,
 PRIMARY KEY (`Toyid`));

CREATE TABLE `quincyninying`.`toy` (
`Toyid` INT NOT NULL,
`ToyName` VARCHAR(50) NULL,
`Toycost` DECIMAL NULL,
PRIMARY KEY (`Toyid`));

在 toy 表上创建一个 BEFORE INSERT 触发器，该触发器将一条记录添加到 toytracking 表，其中包含正在 INSERTED 的 toy 表记录中的信息、硬编码的 ToyAction(将为“INSERT”)以及该记录的当前日期和时间已插入。

ERROR 1054: Unknown column 'inserted' in 'NEW' SQL Statement:
CREATE DEFINER = CURRENT_USER TRIGGER `quincyninying`.`toy_BEFORE_INSERT` BEFORE INSERT ON `toy` 
FOR EACH ROW
BEGIN
    IF new.inserted THEN
        SET @toyaction = 'DELETE';
    ELSE 
        SET @toyaction = 'NEW';
    END IF;

    INSERT INTO `quincyninying`.`toytracking` (toyId, ToyName, ToyCost,     Toyaction, ActionDate)
    VALUES       (new.toyid, new.Toyname, new.Toycost,@Toyaction, now());

END

它向我抛出一个错误，提示“错误 1054:‘新’中插入了未知列”

Answer 1

摆脱 IF new.inserted 测试，因为没有具有该名称的列，只需将 INSERT 硬编码为 ToyAction 的值 列，如您在要求中所述。

CREATE DEFINER = CURRENT_USER TRIGGER `quincyninying`.`toy_BEFORE_INSERT` BEFORE INSERT ON `toy` 
FOR EACH ROW
BEGIN
    INSERT INTO `quincyninying`.`toytracking` (toyId, ToyName, ToyCost, Toyaction, ActionDate)
    VALUES (new.toyid, new.Toyname, new.Toycost, 'INSERT', now());
END