sql语句练习

1.初始化脚本

/*
Navicat MySQL Data Transfer

Source Server         : 123.207.254.158
Source Server Version : 50718
Source Host           : 123.207.254.158:3306
Source Database       : test

Target Server Type    : MYSQL
Target Server Version : 50718
File Encoding         : 65001

Date: 2017-05-12 13:42:48
*/

SET FOREIGN_KEY_CHECKS=0;

-- ----------------------------
-- Table structure for Course
-- ----------------------------
DROP TABLE IF EXISTS `Course`;
CREATE TABLE `Course` (
  `C` int(11) DEFAULT NULL,
  `Cname` varchar(32) DEFAULT NULL,
  `T` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of Course
-- ----------------------------
INSERT INTO `Course` VALUES ('1', '语文', '1');
INSERT INTO `Course` VALUES ('2', '数学', '2');
INSERT INTO `Course` VALUES ('3', '英语', '3');
INSERT INTO `Course` VALUES ('4', '物理', '4');

-- ----------------------------
-- Table structure for Sc
-- ----------------------------
DROP TABLE IF EXISTS `Sc`;
CREATE TABLE `Sc` (
  `S` int(11) DEFAULT NULL,
  `C` int(11) DEFAULT NULL,
  `score` int(11) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of Sc
-- ----------------------------
INSERT INTO `Sc` VALUES ('1', '1', '56');
INSERT INTO `Sc` VALUES ('1', '2', '78');
INSERT INTO `Sc` VALUES ('1', '3', '67');
INSERT INTO `Sc` VALUES ('1', '4', '58');
INSERT INTO `Sc` VALUES ('2', '1', '79');
INSERT INTO `Sc` VALUES ('2', '2', '81');
INSERT INTO `Sc` VALUES ('2', '3', '92');
INSERT INTO `Sc` VALUES ('2', '4', '68');
INSERT INTO `Sc` VALUES ('3', '1', '91');
INSERT INTO `Sc` VALUES ('3', '2', '47');
INSERT INTO `Sc` VALUES ('3', '3', '88');
INSERT INTO `Sc` VALUES ('3', '4', '56');
INSERT INTO `Sc` VALUES ('4', '2', '88');
INSERT INTO `Sc` VALUES ('4', '3', '90');
INSERT INTO `Sc` VALUES ('4', '4', '93');
INSERT INTO `Sc` VALUES ('5', '1', '46');
INSERT INTO `Sc` VALUES ('5', '3', '78');
INSERT INTO `Sc` VALUES ('5', '4', '53');
INSERT INTO `Sc` VALUES ('6', '1', '35');
INSERT INTO `Sc` VALUES ('6', '2', '68');
INSERT INTO `Sc` VALUES ('6', '4', '71');

-- ----------------------------
-- Table structure for Student
-- ----------------------------
DROP TABLE IF EXISTS `Student`;
CREATE TABLE `Student` (
  `S` int(11) DEFAULT NULL,
  `Sname` varchar(32) DEFAULT NULL,
  `Sage` int(11) DEFAULT NULL,
  `Ssex` varchar(8) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of Student
-- ----------------------------
INSERT INTO `Student` VALUES ('1', '刘一', '18', '男');
INSERT INTO `Student` VALUES ('2', '钱二', '19', '女');
INSERT INTO `Student` VALUES ('3', '张三', '17', '男');
INSERT INTO `Student` VALUES ('4', '李四', '18', '女');
INSERT INTO `Student` VALUES ('5', '王五', '17', '男');
INSERT INTO `Student` VALUES ('6', '赵六', '19', '女');

-- ----------------------------
-- Table structure for Teacher
-- ----------------------------
DROP TABLE IF EXISTS `Teacher`;
CREATE TABLE `Teacher` (
  `T` int(11) DEFAULT NULL,
  `Tname` varchar(16) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of Teacher
-- ----------------------------
INSERT INTO `Teacher` VALUES ('1', '叶平');
INSERT INTO `Teacher` VALUES ('2', '贺高');
INSERT INTO `Teacher` VALUES ('3', '杨艳');
INSERT INTO `Teacher` VALUES ('4', '周磊');

• 查询没学过“叶平”老师课的同学的学号、姓名

SELECT s,Sname FROM Student WHERE S NOT IN (
SELECT DISTINCT S FROM Teacher,Course,Sc WHERE Sc.C=Course.C AND Course.T=Teacher.T AND
  Teacher.Tname='叶平'
)

---

• 查询学过“1”并且也学过编号“2”课程的同学的学号、姓名

SELECT Sname,Sc.S FROM Sc,Student WHERE C=1 AND Student.S=Sc.S
AND Student.S IN
(SELECT Sc.S FROM Sc,Student WHERE C=2 AND Student.S=Sc.S)


SELECT Sname,Sc.S FROM Sc,Student WHERE C=1 AND Student.S=Sc.S
AND exists
(SELECT * FROM Sc WHERE C=2 AND Student.S=Sc.S)

---

• 查询学过“叶平”老师所教的所有课的同学的学号、姓名

SELECT Sname,Student.S FROM Student,Sc WHERE Student.S=Sc.S AND Sc.C IN

(SELECT C FROM Teacher ,Course WHERE Teacher.T=Course.T AND Tname='叶平' )

---

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