第一题
/*订单表*/CREATE TABLE `order`( `orderId` VARCHAR(255)COLLATE utf8mb4_0900_ai_ci NOT NULL COMMENT '订单编号',`orderNanme` VARCHAR(255)COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '商品名称',`sale` DECIMAL(10,2)COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '商品销售价',`name` VARCHAR(255)COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '客户姓名',`gender` ENUM('男','女')COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '客户性别',`address` VARCHAR(255)COLLATE utf8mb4_0900_ai_ci DEFAULT NULL COMMENT '客户地址',`date` date DEFAULT NULL COMMENT '送货日期',`install date` date DEFAULT NULL COMMENT '安装日期',PRIMARY KEY (`orderId`),UNIQUE KEY `U_ORDER_ID` (`orderId`) USING BTREE) -- 给 orderId建立一个名叫U_ORDER_ID的唯一索引,索引类型是BTREEENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT '订单表';/*向表中插入两条数据*/INSERT INTO `order` VALUES('y0101202009019875','煤气灶',251.00 ,'李四','男','杭州', '2021-04-04', '2020-04-05');INSERT INTO `order` VALUES('y0101202009019876','电暖气',351.00 ,'李四四','女','杭州', '2021-04-04', '2020-04-05');



第二题
/*房客表建表语句*/CREATE TABLE `guest`( `guest_Number`INT(30)NOT NULL COMMENT '客人编号',`guest_Nanme` VARCHAR(255)DEFAULT NULL COMMENT '客人名称',`guest_gender` ENUM('男','女') COMMENT '性别',`guest_Id` VARCHAR(255) DEFAULT NULL COMMENT '身份证号',`deposit` DECIMAL(10,2) NOT NULL COMMENT '押金',`date1` date DEFAULT NULL COMMENT '入住时间',`date2` date DEFAULT NULL COMMENT '结账时间',`guest_amount`DECIMAL(10,2) NOT NULL COMMENT '总金额',`room_Number`INT(30)NOT NULL COMMENT '客房号', -- 体现房客表与客房表一对一PRIMARY KEY (`guest_Number`),UNIQUE KEY `U_ORDER_ID` (`guest_Number`)) -- 字段建立唯一索引ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT'房客表' ;/*客房表建表语句*/CREATE TABLE `room`( `room_Number`INT(30)NOT NULL COMMENT '客房号',`room_Type` ENUM('双人间','单人间') DEFAULT NULL COMMENT '客房类型',`room_State` VARCHAR(255) DEFAULT NULL COMMENT '客房状态',`room_People` INT DEFAULT NULL COMMENT '入住人数',`room_Price` DECIMAL(10,2) DEFAULT NULL COMMENT '单价',`room_rooms` ENUM('1','2') COMMENT '房间数',`room_amount`DECIMAL(10,2) DEFAULT NULL COMMENT '总金额',PRIMARY KEY (`room_Number`),UNIQUE KEY `U_ROOM_NUMBER` (`room_Number`)) -- 字段建立唯一索引ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT'客房表' ;/*房客入住表建表语句*/CREATE TABLE `room_live`( `id` int(255) NOT NULL AUTO_INCREMENT COMMENT '主键',`guest_Number`INT(30)NOT NULL COMMENT '客人编号', -- 体现房客表和客房表 与 房客入住表 多对一或一对多`room_Number`INT(30)NOT NULL COMMENT '客房号', -- 体现房客表和客房表 与 房客入住表 多对一或一对多PRIMARY KEY (`id`),UNIQUE KEY `U_LIVE_ID` (`id`)) -- 字段建立唯一索引ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT'房客入住表' ;/*插入房客数据*/INSERT INTO `guest`VALUES( 1,'张三','男','310xxxxxxxxxxxxxxx',100.00,'2021-4-4','2021-4-5',60.00,1), (2,'李四四','女','311xxxxxxxxxxxxxxx',100.00,'2021-4-4','2021-4-5',100.00,2), (3,'王五','男','312xxxxxxxxxxxxxxx',100.00,'2021-4-4','2021-4-5',60.00,1), (4,'赵六','男','313xxxxxxxxxxxxxxx',100.00,'2021-4-4','2021-4-5',60.00,1), (5,'张八','男','314xxxxxxxxxxxxxxx',100.00,'2021-4-4','2021-4-5',60.00,1 );/*插入客房数据*/INSERT INTO `room` VALUES( 1,'单人间','已入住',1 ,80.00,1,80.00), (2,'双人间','已入住',4 ,60.00,2,60*4 -- 60一间,4个人240 );/*插入房客表入住表数据*/INSERT INTO `room_live` VALUES( 1,1,1), (2,2,2), (3,3,1), (4,4,1), (5,5,1 );/*查看房客表中数据*/SELECT * FROM `guest`;/*查看客房表中数据*/SELECT * FROM `room`;/*查看房客入住表中数据*/SELECT * FROM `room_live`;



第三题
/*学生表建表语句*/CREATE TABLE `student`( `student_id` INT(11) NOT NULL COMMENT '学号',`student_naem` VARCHAR(255) NOT NULL COMMENT '学生姓名',`student_gender` ENUM('男','女') NOT NULL COMMENT '学生性别',`department_name` VARCHAR(255) NOT NULL COMMENT '系名',PRIMARY KEY (`student_id`),UNIQUE KEY `U_STUDENTI_ID` (`student_id`))ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT'学生表' ;/*院系表建表语句*/CREATE TABLE `department`( `department_name` VARCHAR(255) NOT NULL COMMENT '系名',`department_director` VARCHAR(255) NOT NULL COMMENT '系主任',PRIMARY KEY (`department_name`))ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT'院系表';/*学生成绩表建表语句*/CREATE TABLE `score`( `student_id` INT(11) NOT NULL COMMENT '学号',`student_name` VARCHAR(255) NOT NULL COMMENT '学生姓名',`student_score` DECIMAL(4,2) NOT NULL COMMENT '学生成绩',PRIMARY KEY (`student_id`,`student_name`)) -- 建立学号和学生姓名的联合主键ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci COMMENT'学生成绩表';/*向学生表插入数据*/INSERT INTO `student` VALUES( 20200401,'李小四','男','计科系'), (20200402,'张小兰','女','计科系'), (20200403,'王帅八','男','法律系'), (20200404,'李小四','男','法律系' );/*向院系表插入数据*/INSERT INTO `department` VALUES( '计科系','张宝'), ('法律系','刘德' );/*向学生成绩表插入数据*/INSERT INTO `score` VALUES( 20200401,'高等数学',89), (20200401,'大学英语',90), (20200401,'微机原理',99), (20200402,'高等数学',89), (20200402,'大学英语',90), (20200402,'线性代数',99), (20200403,'高等数学',89), (20200403,'法律基础',98), (20200404,'大学英语',90), (20200404,'法律基础',99 ); /*查看学生表数据*/SELECT * FROM `student`;/*查看院系表数据*/SELECT * FROM `department`;/*查看学生成绩表数据*/SELECT * FROM `score`;


