创建表BookClass, Publisher, Book, Reader, Borrow

好的，以下是创建这些表格的 SQL 命令：

1. 创建表格 BookClass：

CREATE TABLE BookClass (
  ClassID INT NOT NULL PRIMARY KEY,
  ClassName VARCHAR(50) NOT NULL
);

2. 创建表格 Publisher：

CREATE TABLE Publisher (
  PublisherID INT NOT NULL PRIMARY KEY,
  PublisherName VARCHAR(50) NOT NULL,
  PublisherAddress VARCHAR(100) NOT NULL
);

3. 创建表格 Book：

CREATE TABLE Book (
  ISBN VARCHAR(20) NOT NULL PRIMARY KEY,
  BookName VARCHAR(100) NOT NULL,
  Author VARCHAR(50) NOT NULL,
  ClassID INT NOT NULL,
  PublisherID INT NOT NULL,
  PublishDate DATE NOT NULL,
  UnitPrice DECIMAL(8,2) NOT NULL,
  CONSTRAINT FK_Book_ClassID FOREIGN KEY (ClassID) REFERENCES BookClass(ClassID),
  CONSTRAINT FK_Book_PublisherID FOREIGN KEY (PublisherID) REFERENCES Publisher(PublisherID)
);

4. 创建表格 Reader：

CREATE TABLE Reader (
  ReaderID INT NOT NULL PRIMARY KEY,
  ReaderName VARCHAR(50) NOT NULL,
  ReaderSex VARCHAR(10) NOT NULL,
  ReaderBirth DATE NOT NULL,
  ReaderAddress VARCHAR(100) NOT NULL,
  ReaderPhone VARCHAR(20) NOT NULL
);

5. 创建表格 Borrow：

CREATE TABLE Borrow (
  BorrowID INT NOT NULL PRIMARY KEY,
  ReaderID INT NOT NULL,
  ISBN VARCHAR(20) NOT NULL,
  BorrowDate DATE NOT NULL,
  ReturnDate DATE NOT NULL,
  CONSTRAINT FK_Borrow_ReaderID FOREIGN KEY (ReaderID) REFERENCES Reader(ReaderID),
  CONSTRAINT FK_Borrow_ISBN FOREIGN KEY (ISBN) REFERENCES Book(ISBN)
);

以上命令将创建包含这五个表格的数据库 BookDB。