一.网上收集了一些测试题，对于掌握SQL查询语句。

 /*

  Navicat MySQL Data Transfer

  Source Server         : lizebo's MYSQL

  Source Server Type    : MySQL

  Source Server Version : 50720

  Source Host           : localhost:3306

  Source Schema         : sql练习

  Target Server Type    : MySQL

  Target Server Version : 50720

  File Encoding         : 65001

  Date: 07/11/2017 20:09:05

 */

 SET NAMES utf8mb4;

 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) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,

   PRIMARY KEY (`cid`) USING BTREE

 ) ENGINE = InnoDB AUTO_INCREMENT = 5 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

 -- ----------------------------

 -- 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) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,

   `teacher_id` int(11) NOT NULL,

   PRIMARY KEY (`cid`) USING BTREE,

   INDEX `fk_course_teacher`(`teacher_id`) USING BTREE,

   CONSTRAINT `fk_course_teacher` FOREIGN KEY (`teacher_id`) REFERENCES `teacher` (`tid`) ON DELETE RESTRICT ON UPDATE RESTRICT

 ) ENGINE = InnoDB AUTO_INCREMENT = 5 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

 -- ----------------------------

 -- 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`) USING BTREE,

   INDEX `fk_score_student`(`student_id`) USING BTREE,

   INDEX `fk_score_course`(`course_id`) USING BTREE,

   CONSTRAINT `fk_score_course` FOREIGN KEY (`course_id`) REFERENCES `course` (`cid`) ON DELETE RESTRICT ON UPDATE RESTRICT,

   CONSTRAINT `fk_score_student` FOREIGN KEY (`student_id`) REFERENCES `student` (`sid`) ON DELETE RESTRICT ON UPDATE RESTRICT

 ) ENGINE = InnoDB AUTO_INCREMENT = 53 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

 -- ----------------------------

 -- 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) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,

   `class_id` int(11) NOT NULL,

   `sname` varchar(32) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,

   PRIMARY KEY (`sid`) USING BTREE,

   INDEX `fk_class`(`class_id`) USING BTREE,

   CONSTRAINT `fk_class` FOREIGN KEY (`class_id`) REFERENCES `class` (`cid`) ON DELETE RESTRICT ON UPDATE RESTRICT

 ) ENGINE = InnoDB AUTO_INCREMENT = 17 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

 -- ----------------------------

 -- Records of student

 -- ----------------------------

 INSERT INTO `student` VALUES (1, '男', 1, '理解');

 INSERT INTO `student` VALUES (2, '女', 1, '钢蛋');

 INSERT INTO `student` VALUES (3, '男', 1, '张三');

 INSERT INTO `student` VALUES (4, '男', 1, '张一');

 INSERT INTO `student` VALUES (5, '女', 1, '张二');

 INSERT INTO `student` VALUES (6, '男', 1, '张四');

 INSERT INTO `student` VALUES (7, '女', 2, '铁锤');

 INSERT INTO `student` VALUES (8, '男', 2, '李三');

 INSERT INTO `student` VALUES (9, '男', 2, '李一');

 INSERT INTO `student` VALUES (10, '女', 2, '李二');

 INSERT INTO `student` VALUES (11, '男', 2, '李四');

 INSERT INTO `student` VALUES (12, '女', 3, '如花');

 INSERT INTO `student` VALUES (13, '男', 3, '刘三');

 INSERT INTO `student` VALUES (14, '男', 3, '刘一');

 INSERT INTO `student` VALUES (15, '女', 3, '刘二');

 INSERT INTO `student` VALUES (16, '男', 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) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,

   PRIMARY KEY (`tid`) USING BTREE

 ) ENGINE = InnoDB AUTO_INCREMENT = 6 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

 -- ----------------------------

 -- 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;

二.查询题

1.查询平均成绩大于60分的同学的学号和平均成绩。（由于一个同学可能选择了多个课程，我们要先查询大于60分的同学就必须分组；得到大于60分的同学；最后查询他们的学号和平均成绩）

2.查询学生的平均分，姓名，student_id;

3.根据上面的查询结果我们可以进行子查询出student_id和avg(num)

SQL测试题的更多相关文章

  1. Mysql学习---SQL测试题之表结构

    创建表结果和数据准备[直接执行即可] /* Navicat MySQL Data Transfer Source Server : ftl1012 Source Server Version : 50 ...

  2. Mysql 系统学习梳理_【All】

    0.Linux学习---CentOS 7编译安装MySQL 8.0 1.Mysql学习---SQL语言的四大分类 2.Mysql学习---基础操作学习 3.Mysql学习---基础操作学习2 4.My ...

  3. 老男孩Python全栈第2期+课件笔记【高清完整92天整套视频教程】

    点击了解更多Python课程>>> 老男孩Python全栈第2期+课件笔记[高清完整92天整套视频教程] 课程目录 ├─day01-python 全栈开发-基础篇 │ 01 pyth ...

  4. SQL server 数据库测试题

  5. PHP测试题讲解（20161027）

    注: 关联数组 关联数组,它的每个 ID 键都关联一个值.在存储有关具体命名的值的数据时,使用数值数组不是最好的做法.通过关联数组,我们可以把值作为键,并向它们赋值. 例子 1 在本例中,我们使用一个 ...

  6. SQL数据库基础知识-巩固篇<一>

    SQL数据库基础知识-巩固篇<一>... =============== 首先展示两款我个人很喜欢的数据库-专用于平时个人SQL技术的练习<特点:体积小,好安装和好卸载,功能完全够用 ...

  7. FFMS SQL文件执行错误

    [mysql] # 设置mysql客户端默认字符集 default-character-set=utf8 [mysqld] #设置3306端口 port = 3306 # 设置mysql的安装目录 b ...

  8. 关于分组查询的一道sql题

    背景:想做一道sql的测试题,题目为: 按照角色分组算出每个角色按有办公室和没办公室的统计人数(列出角色,数量,有无办公室,注意一个角色如果部分有办公室,部分没有需分开统计) 如下,构造测试环境与对应 ...

  9. 最近帮客户实施的基于SQL Server AlwaysOn跨机房切换项目

    最近帮客户实施的基于SQL Server AlwaysOn跨机房切换项目 最近一个来自重庆的客户找到走起君,客户的业务是做移动互联网支付,是微信支付收单渠道合作伙伴,数据库里存储的是支付流水和交易流水 ...

随机推荐

  1. C#编译器和CLI的安装

    为了完成C#程序编译和运行,需要安装代码对应版本的编译器和CLI(公共语言框架)平台. (部分内容摘自<C#本质论>) 针对主流的CLI平台(Microsoft .NET),有两种安装方案 ...

  2. 解决Nginx+Tomcat时ContextPath不同的问题

    1        问题描述 项目前端模板使用Thymeleaf,在对各种URL进行格式化输出时,都使用@{uri}代码.它会自动读取项目部署的虚拟路径,添加到URI的前端输出. 真实测试和生产环境中, ...

  3. VirtualBox虚拟磁盘文件.vdi从C盘转移到D盘

    起因很简单:C盘快爆满了,用PS修个图的都无法保存.用Everything搜索了下C盘,发现有个WIN7的.vdi文件,竟然占据了15G的宝贵C盘空间!记得有一次,我直接把.vdi文件转移,然后在Vi ...

  4. 【译】10分钟学会Pandas

    十分钟学会Pandas 这是关于Pandas的简短介绍主要面向新用户.你可以参考Cookbook了解更复杂的使用方法 习惯上,我们这样导入: In [1]: import pandas as pd I ...

  5. 中高级JavaScript易错面试题

    写出下题的输出 1.函数的实参与形参length var length = 10; function fn() { console.log(this.length); } var obj = { le ...

  6. Problem K

    Problem Description The local toy store sells small fingerpainting kits with between three and twelv ...

  7. Linux系统安装_Centos6.9

    第1章 虚拟机安装  1.1 镜像下载 1.1.1 新版本下载 http://mirrors.aliyun.com  #阿里云官方镜像站点 1.1.2 旧版本下载 http://vault.cento ...

  8. 一场围绕着‘Deeping Learning’的高考

    Deep Learning的基本思想和方法 实际生活中,人们为了解决一个问题,如对象的分类(对象可是是文档.图像等),首先必须做的事情是如何来表达一个对象,即必须抽取一些特征来表示一个对象,如文本的处 ...

  9. Golang源码探索(二) 协程的实现原理

    Golang最大的特色可以说是协程(goroutine)了, 协程让本来很复杂的异步编程变得简单, 让程序员不再需要面对回调地狱, 虽然现在引入了协程的语言越来越多, 但go中的协程仍然是实现的是最彻 ...

  10. 【Arduino】使用LCD1602和DHT11制作温湿度显示器

    材料: 1.DHT11 2.LCD1602 3.LCD1602 转接板 4.Arduino UNO 5.Arduino 传感器扩展版 那个Arduino UNO 我当初挑类个便宜的山寨货买,结果发来和 ...