编辑代码

CREATE DATABASE bms CHARACTER SET utf8mb4;
USE bms
CREATE TABLE user  (
	id INT PRIMARY KEY AUTO_INCREMENT,
	name VARCHAR(20) NOT NULL UNIQUE,
	state CHAR(1) NOT NULL DEFAULT 0
);
CREATE TABLE book  (
	id INT  PRIMARY KEY AUTO_INCREMENT,
	name VARCHAR(20) NOT NULL UNIQUE,
	price DECIMAL(6, 2)  NOT NULL,
	upload_time DATETIME NOT NULL,
	borrower_id INT ,
	borrow_time DATETIME,
	state CHAR(1) NOT NULL DEFAULT 0
);
CREATE TABLE record  (
  id INT  PRIMARY KEY AUTO_INCREMENT,
  book_id INT NOT NULL,
  borrower_id INT NOT NULL,
  borrow_time DATETIME NOT NULL,
  remand_time DATETIME NOT NULL
);