Question

我的SQL脚本有一个奇怪的问题，我希望有人可以帮我解决。

我使用

创建了一个数据库

IF EXISTS (SELECT name
    FROM sysdatabases
    WHERE name = 'travel')
    DROP DATABASE travel
    GO
    CREATE DATABASE travel
GO

USE travel
GO

然后我创建了3个表，如下所示

CREATE TABLE customer
(
    customerID INT,
    lastname VARCHAR(70) NOT NULL,
    firstname VARCHAR(70) NOT NULL,
    phone VARCHAR(10) CONSTRAINT phoneCheck CHECK ((phone LIKE '[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]')),
    category VARCHAR(7) NOT NULL CONSTRAINT categoryDefault DEFAULT 'A',
    CONSTRAINT categoryCheck CHECK (category IN ('A', 'B', 'C')),

    CONSTRAINT customerPK
        PRIMARY KEY (customerID)
)

CREATE TABLE package    /*Still need to do the Zero Padding*/
(
    packageCode VARCHAR(6),
    destination VARCHAR(70),
    CONSTRAINT packageCodeCheck CHECK (packageCode LIKE ('YFK%')),
    price MONEY NOT NULL CONSTRAINT priceCheck CHECK ((price BETWEEN 1000 AND 10000)),
    passportRequired VARCHAR(7) NOT NULL CONSTRAINT passportRequiredDefault DEFAULT 'Y',
    CONSTRAINT passportCheck CHECK (passportRequired IN ('Y', 'N')),

    CONSTRAINT packagePK
        PRIMARY KEY (packageCode)
)

CREATE TABLE booking    /*Still need to do the Customer and Package delete*/
(
    customerID VARCHAR(6),
    bookingDate VARCHAR(70) NOT NULL DEFAULT GETDATE(),
    amountPaid MONEY CONSTRAINT amountPaidDefault DEFAULT 0.00,

    CONSTRAINT bookingPK
        PRIMARY KEY (customerID)
)

现在是问题所在，我创建了一个触发器，如下所示

GO

CREATE TRIGGER customerDelete ON customer AFTER DELETE
AS
DELETE booking
FROM customer
WHERE customer.customerID = booking.customerID

GO

根据我的理解，它将删除预订中的所有记录...具有匹配的customerID当从客户表中删除记录时。（我是触发器的新手）

我插入样本数据如下所示

INSERT INTO customer
    (customerID, lastname, firstname, phone, category)
VALUES
    (1, 'Picard', 'Corey', 1234567890, 'A'),
    (2, 'Bond', 'Devon', 9876543210, 'B'),
    (3, 'Douglas', 'Bryan', 6549871230, 'C')

INSERT INTO package
    (packageCode, destination, price, passportRequired)
VALUES
    ('YFK001', 'Toronto', 1000.57, 'N'),
    ('YFK002', 'Orlando', 3000.98, 'Y')

INSERT INTO booking
    (customerID, bookingDate, amountPaid)
VALUES
    (1, GETDATE(), 1548),
    (2, GETDATE(), 1586),
    (3, GETDATE(), 1350),
    (4, GETDATE(), 1650)

最后，我使用

从TABLE客户中删除客户，客户ID为1

DELETE customer
    WHERE customerID = 1

但是，当我尝试使用

查看结果时

SELECT * FROM customer
    --WHERE customerID = 1 OR customerID = 2 OR customerID = 3

SELECT * FROM package
    --WHERE packageCode = 'YFK001' OR packageCode = 'YFK002'

SELECT * FROM booking
    --WHERE customerID = 1 OR customerID = 2 OR customerID = 3 OR customerID = 4

显示客户ID为1和4的预订。

你能让我知道我做错了吗？

触发器主要用于删除我们从客户表中删除的客户的同一客户ID的预订。

非常感谢所有帮助。

谢谢，布赖恩

Answer 1

将删除更改为：

DELETE B
FROM booking B
INNER JOIN DELETED D
    ON B.customerID = D.customerID;

Answer 2

我的答案不是触发器，[如果您特别想使用触发器，那么您可以使用Lamak＆amp;普拉迪普的答案] 在这里，你可以做的最好的方法是在你的情况下使用外键上的Cacade

这是您的查询我刚刚在其中更新了级联

CREATE TABLE customer
(
    customerID INT,
    lastname VARCHAR(70) NOT NULL,
    firstname VARCHAR(70) NOT NULL,
    phone VARCHAR(10) CONSTRAINT phoneCheck CHECK ((phone LIKE '[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]')),
    category VARCHAR(7) NOT NULL CONSTRAINT categoryDefault DEFAULT 'A',
    CONSTRAINT categoryCheck CHECK (category IN ('A', 'B', 'C')),

    CONSTRAINT customerPK
        PRIMARY KEY (customerID)
)

CREATE TABLE package    /*Still need to do the Zero Padding*/
(
    packageCode VARCHAR(6),
    destination VARCHAR(70),
    CONSTRAINT packageCodeCheck CHECK (packageCode LIKE ('YFK%')),
    price MONEY NOT NULL CONSTRAINT priceCheck CHECK ((price BETWEEN 1000 AND 10000)),
    passportRequired VARCHAR(7) NOT NULL CONSTRAINT passportRequiredDefault DEFAULT 'Y',
    CONSTRAINT passportCheck CHECK (passportRequired IN ('Y', 'N')),

    CONSTRAINT packagePK
        PRIMARY KEY (packageCode)
 ON DELETE CASCADE
       ON UPDATE CASCADE
)

CREATE TABLE booking    /*Still need to do the Customer and Package delete*/
(
    customerID VARCHAR(6),
    bookingDate VARCHAR(70) NOT NULL DEFAULT GETDATE(),
    amountPaid MONEY CONSTRAINT amountPaidDefault DEFAULT 0.00,

    CONSTRAINT bookingPK
        PRIMARY KEY (customerID) 
ON DELETE CASCADE
       ON UPDATE CASCADE
)

这样当您删除或更新[keyvalue]时，持有主键的表的任何条目都将更新其相关的外国孩子

SQL Server触发器向后运行

2 个答案: