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MYSQL-01-作业题

时间:2017-09-17 13:24:06      阅读:218      评论:0      收藏:0      [点我收藏+]

标签:date   连表   host   姓名   student   local   logs   weight   end   

学生选课系统

设计表关系

技术分享

创建表和插入数据

技术分享
/*
Navicat MySQL Data Transfer

Source Server         : localhost_3306
Source Server Version : 50719
Source Host           : localhost:3306
Source Database       : oldbo

Target Server Type    : MYSQL
Target Server Version : 50719
File Encoding         : 65001

Date: 2017-07-26 15:46:16
*/

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for class
-- ----------------------------
DROP TABLE IF EXISTS `class`;
CREATE TABLE `class` (
  `cid` int(11) NOT NULL AUTO_INCREMENT,
  `caption` varchar(32) NOT NULL,
  PRIMARY KEY (`cid`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of class
-- ----------------------------
INSERT INTO `class` VALUES (1, 三年二班);
INSERT INTO `class` VALUES (2, 三年三班);
INSERT INTO `class` VALUES (3, 一年二班);
INSERT INTO `class` VALUES (4, 二年九班);

-- ----------------------------
-- Table structure for course
-- ----------------------------
DROP TABLE IF EXISTS `course`;
CREATE TABLE `course` (
  `cid` int(11) NOT NULL AUTO_INCREMENT,
  `cname` varchar(32) NOT NULL,
  `teacher_id` int(11) NOT NULL,
  PRIMARY KEY (`cid`),
  KEY `fk_course_teacher` (`teacher_id`),
  CONSTRAINT `fk_course_teacher` FOREIGN KEY (`teacher_id`) REFERENCES `teacher` (`tid`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of course
-- ----------------------------
INSERT INTO `course` VALUES (1, 生物, 1);
INSERT INTO `course` VALUES (2, 物理, 2);
INSERT INTO `course` VALUES (3, 体育, 3);
INSERT INTO `course` VALUES (4, 美术, 2);

-- ----------------------------
-- Table structure for score
-- ----------------------------
DROP TABLE IF EXISTS `score`;
CREATE TABLE `score` (
  `sid` int(11) NOT NULL AUTO_INCREMENT,
  `student_id` int(11) NOT NULL,
  `course_id` int(11) NOT NULL,
  `num` int(11) NOT NULL,
  PRIMARY KEY (`sid`),
  KEY `fk_score_student` (`student_id`),
  KEY `fk_score_course` (`course_id`),
  CONSTRAINT `fk_score_course` FOREIGN KEY (`course_id`) REFERENCES `course` (`cid`),
  CONSTRAINT `fk_score_student` FOREIGN KEY (`student_id`) REFERENCES `student` (`sid`)
) ENGINE=InnoDB AUTO_INCREMENT=53 DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of score
-- ----------------------------
INSERT INTO `score` VALUES (1, 1, 1, 10);
INSERT INTO `score` VALUES (2, 1, 2, 9);
INSERT INTO `score` VALUES (5, 1, 4, 66);
INSERT INTO `score` VALUES (6, 2, 1, 8);
INSERT INTO `score` VALUES (8, 2, 3, 68);
INSERT INTO `score` VALUES (9, 2, 4, 99);
INSERT INTO `score` VALUES (10, 3, 1, 77);
INSERT INTO `score` VALUES (11, 3, 2, 66);
INSERT INTO `score` VALUES (12, 3, 3, 87);
INSERT INTO `score` VALUES (13, 3, 4, 99);
INSERT INTO `score` VALUES (14, 4, 1, 79);
INSERT INTO `score` VALUES (15, 4, 2, 11);
INSERT INTO `score` VALUES (16, 4, 3, 67);
INSERT INTO `score` VALUES (17, 4, 4, 100);
INSERT INTO `score` VALUES (18, 5, 1, 79);
INSERT INTO `score` VALUES (19, 5, 2, 11);
INSERT INTO `score` VALUES (20, 5, 3, 67);
INSERT INTO `score` VALUES (21, 5, 4, 100);
INSERT INTO `score` VALUES (22, 6, 1, 9);
INSERT INTO `score` VALUES (23, 6, 2, 100);
INSERT INTO `score` VALUES (24, 6, 3, 67);
INSERT INTO `score` VALUES (25, 6, 4, 100);
INSERT INTO `score` VALUES (26, 7, 1, 9);
INSERT INTO `score` VALUES (27, 7, 2, 100);
INSERT INTO `score` VALUES (28, 7, 3, 67);
INSERT INTO `score` VALUES (29, 7, 4, 88);
INSERT INTO `score` VALUES (30, 8, 1, 9);
INSERT INTO `score` VALUES (31, 8, 2, 100);
INSERT INTO `score` VALUES (32, 8, 3, 67);
INSERT INTO `score` VALUES (33, 8, 4, 88);
INSERT INTO `score` VALUES (34, 9, 1, 91);
INSERT INTO `score` VALUES (35, 9, 2, 88);
INSERT INTO `score` VALUES (36, 9, 3, 67);
INSERT INTO `score` VALUES (37, 9, 4, 22);
INSERT INTO `score` VALUES (38, 10, 1, 90);
INSERT INTO `score` VALUES (39, 10, 2, 77);
INSERT INTO `score` VALUES (40, 10, 3, 43);
INSERT INTO `score` VALUES (41, 10, 4, 87);
INSERT INTO `score` VALUES (42, 11, 1, 90);
INSERT INTO `score` VALUES (43, 11, 2, 77);
INSERT INTO `score` VALUES (44, 11, 3, 43);
INSERT INTO `score` VALUES (45, 11, 4, 87);
INSERT INTO `score` VALUES (46, 12, 1, 90);
INSERT INTO `score` VALUES (47, 12, 2, 77);
INSERT INTO `score` VALUES (48, 12, 3, 43);
INSERT INTO `score` VALUES (49, 12, 4, 87);
INSERT INTO `score` VALUES (52, 13, 3, 87);

-- ----------------------------
-- Table structure for student
-- ----------------------------
DROP TABLE IF EXISTS `student`;
CREATE TABLE `student` (
  `sid` int(11) NOT NULL AUTO_INCREMENT,
  `gender` char(1) NOT NULL,
  `class_id` int(11) NOT NULL,
  `sname` varchar(32) NOT NULL,
  PRIMARY KEY (`sid`),
  KEY `fk_class` (`class_id`),
  CONSTRAINT `fk_class` FOREIGN KEY (`class_id`) REFERENCES `class` (`cid`)
) ENGINE=InnoDB AUTO_INCREMENT=17 DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of student
-- ----------------------------
INSERT INTO `student` VALUES (1, , 1, 理解);
INSERT INTO `student` VALUES (2, , 1, 钢蛋);
INSERT INTO `student` VALUES (3, , 1, 张三);
INSERT INTO `student` VALUES (4, , 1, 张一);
INSERT INTO `student` VALUES (5, , 1, 张二);
INSERT INTO `student` VALUES (6, , 1, 张四);
INSERT INTO `student` VALUES (7, , 2, 铁锤);
INSERT INTO `student` VALUES (8, , 2, 李三);
INSERT INTO `student` VALUES (9, , 2, 李一);
INSERT INTO `student` VALUES (10, , 2, 李二);
INSERT INTO `student` VALUES (11, , 2, 李四);
INSERT INTO `student` VALUES (12, , 3, 如花);
INSERT INTO `student` VALUES (13, , 3, 刘三);
INSERT INTO `student` VALUES (14, , 3, 刘一);
INSERT INTO `student` VALUES (15, , 3, 刘二);
INSERT INTO `student` VALUES (16, , 3, 刘四);

-- ----------------------------
-- Table structure for teacher
-- ----------------------------
DROP TABLE IF EXISTS `teacher`;
CREATE TABLE `teacher` (
  `tid` int(11) NOT NULL AUTO_INCREMENT,
  `tname` varchar(32) NOT NULL,
  PRIMARY KEY (`tid`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of teacher
-- ----------------------------
INSERT INTO `teacher` VALUES (1, 张磊老师);
INSERT INTO `teacher` VALUES (2, 李平老师);
INSERT INTO `teacher` VALUES (3, 刘海燕老师);
INSERT INTO `teacher` VALUES (4, 朱云海老师);
INSERT INTO `teacher` VALUES (5, 李杰老师);
SET FOREIGN_KEY_CHECKS=1;
View Code

查询条件

1、查询所有的课程的名称以及对应的任课老师姓名
 
2、查询学生表中男女生各有多少人
 
3、查询物理成绩等于100的学生的姓名
 
4、查询平均成绩大于八十分的同学的姓名和平均成绩
 
5、查询所有学生的学号,姓名,选课数,总成绩
 
6、 查询姓李老师的个数
 
7、 查询没有报李平老师课的学生姓名
 
8、 查询物理课程比生物课程高的学生的学号
 
9、 查询没有同时选修物理课程和体育课程的学生姓名
 
10、查询挂科超过两门(包括两门)的学生姓名和班级
 
11 、查询选修了所有课程的学生姓名
 
12、查询李平老师教的课程的所有成绩记录
  
13、查询全部学生都选修了的课程号和课程名
 
14、查询每门课程被选修的次数
 
15、查询之选修了一门课程的学生姓名和学号
 
16、查询所有学生考出的成绩并按从高到低排序(成绩去重)
 
17、查询平均成绩大于85的学生姓名和平均成绩
 
18、查询生物成绩不及格的学生姓名和对应生物分数
 
19、查询在所有选修了李平老师课程的学生中,这些课程(李平老师的课程,不是所有课程)平均成绩最高的学生姓名

  参考答案:

技术分享
1SELECT cname,tname FROM course LEFT JOIN teacher on course.teacher_id=teacher.tid
 
2SELECT gender 性别 ,COUNT(gender) 人数 from student GROUP BY gender;
 
3SELECT sname from student where sid in (SELECT student_id from score LEFT JOIN course
                  ON  score.course_id=course.cid WHERE num=100 AND course.cname="物理");
 
 
4SELECT sname 姓名,平均成绩 from student RIGHT JOIN
          (SELECT student_id,avg(num) 平均成绩
          from score  GROUP BY student_id
          HAVING avg(num)>80) as A
          on student.sid=A.student_id;
 
 
5SELECT  student_id 学号,sname 姓名,COUNT(course_id) 课程数,SUM(num) 总分 FROM score
                  LEFT JOIN student ON score.student_id=student.sid GROUP BY student_id;
 
7SELECT * FROM student
                    WHERE sid not in
                   (SELECT student_id FROM score WHERE course_id in
                   (SELECT cid FROM course LEFT JOIN teacher ON teacher.tid=course.teacher_id
                    WHERE tname like "李平%"))
 
8SELECT * FROM
 
        (SELECT * FROM score LEFT JOIN course
                ON score.course_id=course.cid WHERE cname="生物") as A
 
    INNER JOIN
 
        (SELECT * FROM score LEFT JOIN course
                ON score.course_id=course.cid WHERE cname="物理") as B
 
    ON A.student_id=B.student_id
 
    WHERE a.num<b.num
 
 
 
9SELECT sname from student
                 WHERE sid NOT IN (SELECT student_id FROM score LEFT JOIN course
                 ON score.course_id=course.cid
                 WHERE cname=体育  OR cname=物理
                 GROUP BY student_id
                 HAVING COUNT(course_id)>1) ;
 
10SELECT sname,gender from student
                          WHERE sid in (SELECT student_id from score WHERE num<60
                          GROUP BY student_id
                          HAVING COUNT(student_id)>1);
 
 
11SELECT sid 学号,sname 姓名 from student
                WHERE sid in (SELECT student_id FROM score
                GROUP BY student_id
                HAVING COUNT(student_id)!= (SELECT COUNT(cid) FROM course))
 
12SELECT * FROM score
                WHERE course_id NOT IN (SELECT cid from teacher INNER JOIN course
                on teacher.tid=course.teacher_id
                WHERE teacher.tname LIKE "李平%");
 
 
13SELECT course_id from score
                GROUP BY course_id
                HAVING COUNT(course_id)=(SELECT COUNT(sid) FROM student)
 
 
14--  SELECT course_id,COUNT(course_id) from score GROUP BY course_id
 
 
       SELECT cname,COUNT(course_id) FROM score LEFT JOIN course
                        ON score.course_id=course.cid GROUP BY course_id
 
15SELECT sid,sname FROM student 
                    WHERE sid in (SELECT student_id from score
                    GROUP BY student_id
            HAVING COUNT(sid)=1);
 
 
16SELECT DISTINCT num FROM score ORDER BY num DESC17SELECT sname from student
                    WHERE sid in (SELECT student_id FROM score
                    GROUP BY student_id 
                    HAVING AVG(num)>85)
       注意:用这种方式我们无法查看对应的平均成绩,所以不得不使用连表:
       SELECT sname,AVG(num) FROM student LEFT JOIN score
                    ON student.sid=score.student_id
                    GROUP BY student_id HAVING AVG(num)>85;
 
 
18SELECT sname 姓名,num 生物成绩 FROM score
                 LEFT JOIN course ON score.course_id=course.cid
                 LEFT JOIN student ON score.student_id=student.sid
 
                 WHERE score.num<60 AND cname="生物";
 
 
19SELECT student_id,avg(num),sname FROM score
                 LEFT JOIN student ON score.student_id=student.sid
                     WHERE course_id in (SELECT cid FROM course
                     LEFT JOIN teacher ON teacher.tid=course.teacher_id WHERE tname LIKE "李平%")
                     GROUP BY student_id
                 ORDER BY AVG(num) DESC
                 LIMIT 1
View Code

 

MYSQL-01-作业题

标签:date   连表   host   姓名   student   local   logs   weight   end   

原文地址:http://www.cnblogs.com/xiechao621/p/7534912.html

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