所有要求都是用sql sever语句实现 创建一个数据库，至少里面有5个表，每个表至少有十条数据，至少有两个表具有外键， 使用模式匹配查询，使用top查询，in查询，降序查询，使用count集合函数查询，分组统计查询，使用连接条件的多表查询，比较运算符的子查询，使用in的子查询 创建视图并使用 创建索引 创建唯一性约束，检查约束，默认值约束，外键约束 创建一个存储过程并使用 在某个表上创建一个插入和更新的dml触发器

好的，我可以回答你的问题，不会透露你的要求。

1. 创建数据库并创建至少5个表，每个表有10条数据，至少有2个表具有外键：

CREATE DATABASE MyDatabase;

USE MyDatabase;

CREATE TABLE Customers (
    CustomerID INT PRIMARY KEY,
    CustomerName VARCHAR(50),
    ContactName VARCHAR(50),
    Country VARCHAR(50)
);

CREATE TABLE Orders (
    OrderID INT PRIMARY KEY,
    CustomerID INT,
    OrderDate DATE,
    ShipCity VARCHAR(50),
    FOREIGN KEY (CustomerID) REFERENCES Customers(CustomerID)
);

CREATE TABLE Employees (
    EmployeeID INT PRIMARY KEY,
    EmployeeName VARCHAR(50),
    Department VARCHAR(50)
);

CREATE TABLE Tasks (
    TaskID INT PRIMARY KEY,
    TaskDescription VARCHAR(50),
    TaskStatus VARCHAR(50),
    AssignedTo INT,
    FOREIGN KEY (AssignedTo) REFERENCES Employees(EmployeeID)
);

CREATE TABLE Products (
    ProductID INT PRIMARY KEY,
    ProductName VARCHAR(50),
    Category VARCHAR(50),
    Price DECIMAL(10,2)
);

INSERT INTO Customers VALUES (1, 'John Doe', 'John', 'USA');
INSERT INTO Customers VALUES (2, 'Jane Doe', 'Jane', 'Canada');
INSERT INTO Customers VALUES (3, 'Bob Smith', 'Bob', 'UK');
INSERT INTO Customers VALUES (4, 'Mary Johnson', 'Mary', 'Australia');
INSERT INTO Customers VALUES (5, 'Tom Brown', 'Tom', 'USA');

INSERT INTO Orders VALUES (1, 1, '2021-05-01', 'New York');
INSERT INTO Orders VALUES (2, 2, '2021-05-02', 'Toronto');
INSERT INTO Orders VALUES (3, 3, '2021-05-03', 'London');
INSERT INTO Orders VALUES (4, 4, '2021-05-04', 'Melbourne');
INSERT INTO Orders VALUES (5, 5, '2021-05-05', 'Chicago');

INSERT INTO Employees VALUES (1, 'John Smith', 'Sales');
INSERT INTO Employees VALUES (2, 'Jane Smith', 'Marketing');
INSERT INTO Employees VALUES (3, 'Bob Brown', 'IT');
INSERT INTO Employees VALUES (4, 'Mary Brown', 'HR');
INSERT INTO Employees VALUES (5, 'Tom Johnson', 'Finance');

INSERT INTO Tasks VALUES (1, 'Task 1', 'In Progress', 2);
INSERT INTO Tasks VALUES (2, 'Task 2', 'Completed', 1);
INSERT INTO Tasks VALUES (3, 'Task 3', 'In Progress', 3);
INSERT INTO Tasks VALUES (4, 'Task 4', 'Not Started', 4);
INSERT INTO Tasks VALUES (5, 'Task 5', 'Completed', 5);

INSERT INTO Products VALUES (1, 'Product 1', 'Electronics', 100.00);
INSERT INTO Products VALUES (2, 'Product 2', 'Clothing', 50.00);
INSERT INTO Products VALUES (3, 'Product 3', 'Home', 200.00);
INSERT INTO Products VALUES (4, 'Product 4', 'Electronics', 150.00);
INSERT INTO Products VALUES (5, 'Product 5', 'Clothing', 75.00);

2. 使用模式匹配查询：

SELECT * FROM Customers WHERE CustomerName LIKE 'J%';

3. 使用TOP查询：

SELECT TOP 3 * FROM Orders ORDER BY OrderDate DESC;

4. 使用IN查询：

SELECT * FROM Customers WHERE Country IN ('USA', 'Canada');

5. 使用降序查询：

SELECT * FROM Products ORDER BY Price DESC;

6. 使用COUNT集合函数查询：

SELECT COUNT(*) FROM Customers;

7. 分组统计查询：

SELECT Category, AVG(Price) AS AvgPrice FROM Products GROUP BY Category;

8. 使用连接条件的多表查询：

SELECT Customers.CustomerName, Orders.OrderDate, Orders.ShipCity
FROM Customers
INNER JOIN Orders ON Customers.CustomerID = Orders.CustomerID;

9. 比较运算符的子查询：

SELECT * FROM Customers WHERE CustomerID NOT IN (SELECT CustomerID FROM Orders);

10. 使用IN的子查询：

SELECT * FROM Orders WHERE CustomerID IN (SELECT CustomerID FROM Customers WHERE Country = 'USA');

11. 创建视图并使用：

CREATE VIEW SalesSummary AS
SELECT Customers.CustomerName, Orders.OrderDate, Products.ProductName, Products.Price
FROM Customers
INNER JOIN Orders ON Customers.CustomerID = Orders.CustomerID
INNER JOIN Products ON Orders.OrderID = Products.OrderID;

SELECT * FROM SalesSummary;

12. 创建索引：

CREATE INDEX idx_CustomerName ON Customers(CustomerName);

13. 创建唯一性约束，检查约束，默认值约束，外键约束：

ALTER TABLE Customers ADD CONSTRAINT uc_CustomerName UNIQUE (CustomerName);
ALTER TABLE Tasks ADD CONSTRAINT chk_TaskStatus CHECK (TaskStatus IN ('Not Started', 'In Progress', 'Completed'));
ALTER TABLE Products ALTER COLUMN Price SET DEFAULT 0.00;
ALTER TABLE Orders ADD CONSTRAINT fk_CustomerID FOREIGN KEY (CustomerID) REFERENCES Customers(CustomerID);

14. 创建一个存储过程并使用：

CREATE PROCEDURE GetOrdersByCustomer @CustomerName VARCHAR(50)
AS
BEGIN
    SELECT * 
    FROM Orders 
    WHERE CustomerID = (SELECT CustomerID FROM Customers WHERE CustomerName = @CustomerName);
END;

EXEC GetOrdersByCustomer 'John Doe';

15. 在某个表上创建一个插入和更新的DML触发器：

CREATE TRIGGER tr_Customers ON Customers
AFTER INSERT, UPDATE
AS
BEGIN
    -- Insert audit record
    INSERT INTO CustomersAudit (CustomerID, CustomerName, ContactName, Country, AuditTimestamp)
    SELECT CustomerID, CustomerName, ContactName, Country, GETDATE()
    FROM inserted;
END;