SQL 实验详细源码参考

  1 -- ----------------------------------------------------------------------------------
  2 -- 数据库初始化 （实验二 数据描述、定义实验）
  3 -- ----------------------------------------------------------------------------------
  4 create  database s_13420228;
  5 use s_13420228;
  6 
  7 create table student(
  8     sno varchar(8),
  9     sname varchar(20) not null,  -- 姓名
 10     sage smallint,  -- 年龄
 11     ssex char(8),  -- 性别
 12     sdept varchar(20) ,  -- 所在系
 13     constraint s_pk primary key (sno),  -- 主码
 14     constraint s1 check(sage between 16 and 40),
 15     constraint s2 check(ssex in(‘male‘,‘female‘)),
 16     constraint s3 check(grade between 0 and 100)
 17  );
 18 
 19 create table course(
 20     cno varchar(7),  -- 课程号
 21     cname varchar(50),  -- 课程名
 22     cpno varchar(50),  -- 先行课
 23     ccredit numeric(2,1),  -- 学分,精确存储3.5
 24     constraint c_pk primary key (cno,cname),  -- 主码
 25     constraint s4 foreign key (cpno) references course (cno)  -- 先行课必须要存在
 26 );
 27 
 28 create table sc(  -- 学生选课表
 29     sno varchar(8),  -- 学号
 30     cno varchar(7),  -- 课程号
 31     grade smallint,  -- 成绩
 32     constraint sc_pk primary key (sno,cno),  -- 主码
 33     constraint s5 foreign key (sno) references student(sno) on delete cascade on update cascade,  -- sc中的学号必须存在,级联删除、更新
 34     constraint s6 foreign key (cno) references course(cno) on delete cascade on update cascade -- sc中课程号必须存在
 35 );
 36 
 37 insert into course values(‘01‘, ‘Database‘, null, 4.0);  -- 插入数据 course
 38 insert into course values(‘02‘, ‘Operating System‘, null, 3.5);
 39 insert into course values(‘03‘, ‘Computer Networking‘, null, 4.0);
 40 insert into course values(‘04‘, ‘Data Structures‘, null, 4.0);
 41 insert into course values(‘05‘, ‘The C++ Programming Language‘, null, 4.0);
 42 insert into course values(‘06‘, ‘The C Programming Language‘, null, 4.0);
 43 insert into course values(‘07‘, ‘Physical Principles‘, null, 2.0);
 44 insert into course values(‘08‘, ‘Music Video Production‘, null, 3.0);
 45 insert into course values(‘09‘, ‘Computational Biology‘, null, 3.0);
 46 insert into course values(‘10‘, ‘Genetics‘, null, 3.0); --  Biology
 47 insert into course values(‘11‘, ‘Intro. to Biology‘, null, 3.0);
 48 
 49 insert into student values(‘13420201‘, ‘Zhang‘, 18,‘male‘, ‘CS‘);  -- 插入数据 student
 50 insert into student values(‘13420202‘, ‘Shankar‘, 20,‘male‘, ‘CS‘);
 51 insert into student values(‘13420203‘, ‘Brandt‘, 18,‘male‘, ‘CS‘);
 52 insert into student values(‘13420204‘, ‘Chavez‘, 19,‘female‘, ‘CS‘);
 53 insert into student values(‘13312205‘, ‘Peltier‘, 21,‘female‘, ‘Music‘);
 54 insert into student values(‘13312213‘, ‘Levy‘, 20,‘female‘, ‘Music‘);
 55 insert into student values(‘13312137‘, ‘Williams‘,20, ‘male‘, ‘Music‘);
 56 insert into student values(‘13523111‘, ‘Bourikas‘, 19,‘male‘, ‘Biology‘);
 57 insert into student values(‘13523222‘, ‘Smith‘, 19,‘male‘, ‘Biology‘);
 58 insert into student values(‘13453334‘, ‘Snow‘, 19,‘male‘, ‘Physics‘);
 59 
 60 insert into sc values(‘13420201‘, ‘01‘, 80);  -- 插入数据 sc  CS
 61 insert into sc values(‘13420201‘, ‘02‘, 70);
 62 insert into sc values(‘13420201‘, ‘03‘, 90);
 63 insert into sc values(‘13420201‘, ‘04‘, 40);
 64 insert into sc values(‘13420201‘, ‘05‘, 60);
 65 insert into sc values(‘13420201‘, ‘06‘, 90);
 66 
 67 insert into sc values(‘13420202‘, ‘01‘, 80);
 68 insert into sc values(‘13420202‘, ‘03‘, 90);
 69 insert into sc values(‘13420202‘, ‘04‘, 30);
 70 insert into sc values(‘13420202‘, ‘05‘, 70);
 71 insert into sc values(‘13420202‘, ‘06‘, 90);
 72 
 73 insert into sc values(‘13420203‘, ‘01‘, 80);
 74 insert into sc values(‘13420203‘, ‘02‘, 90);
 75 insert into sc values(‘13420203‘, ‘03‘, 90);
 76 insert into sc values(‘13420203‘, ‘04‘, 85);
 77 insert into sc values(‘13420203‘, ‘05‘, 75);
 78 insert into sc values(‘13420203‘, ‘06‘, 90);
 79 
 80 insert into sc values(‘13420204‘, ‘01‘, 55);
 81 insert into sc values(‘13420204‘, ‘02‘, 55);
 82 insert into sc values(‘13420204‘, ‘03‘, 90);
 83 insert into sc values(‘13420204‘, ‘04‘, 55);
 84 insert into sc values(‘13420204‘, ‘05‘, 70);
 85 insert into sc values(‘13420204‘, ‘06‘, 90);
 86 
 87 insert into sc values(‘13312205‘, ‘08‘, 90);  -- Music
 88 insert into sc values(‘13312213‘, ‘08‘, 60);
 89 insert into sc values(‘13312137‘, ‘08‘, 60);
 90 
 91 insert into sc values(‘13523111‘, ‘09‘, 60);  -- Biology
 92 insert into sc values(‘13523111‘, ‘10‘, 59);
 93 insert into sc values(‘13523111‘, ‘11‘, 80);
 94 
 95 insert into sc values(‘13453334‘, ‘07‘, 70);  -- Physics
 96 
 97 update course set cpno = ‘04‘ where cno = ‘01‘;  -- 更新 course
 98 update course set cpno = ‘04‘ where cno = ‘02‘;
 99 update course set cpno = ‘05‘ where cno = ‘03‘;
100 update course set cpno = ‘05‘ where cno = ‘04‘;
101 update course set cpno = ‘06‘ where cno = ‘05‘;
102 
103 -- --------------------初始化完成----------------------------------------------------------
104 
105 -- 建立索引可以加快查询速度
106 create index grade_index on sc(grade);  -- 多值索引
107 create unique index sno_index on student(sno);  -- 唯一索引，每一个索引值只对应一个唯一的数据记录
108 drop index grade_index on sc;  -- 删除索引
109 drop index sno_index on student;
110 
111 alter table student add birthday date;  -- 添加属性列
112 alter table student drop sage;  -- 删除属性列
113 
114 alter table course drop foreign key s3;  -- 删除约束s3
115 alter table course add constraint s3 foreign key (cpno) references course (cno)
116 on delete cascade on update cascade; -- 先行课必须要存在,添加级联删除、更新
117 
118 delete from course where cno = ‘04‘;  -- 删除特定元组
119 
120 delete from student;  -- 删除关系student的所有元组
121 delete from sc;
122 delete from course;
123 drop table student;  -- 完全删除student，包括student这个模式及其所有元组
124 drop table sc;
125 drop table course;
126 
127 -- ----------------------------------------------------------------------------------
128 -- (实验三 数据更新实验)
129 -- ----------------------------------------------------------------------------------
130 
131 -- 插入某个学生的选课信息(外码约束，拒绝的)
132 insert into sc values(‘13436214‘,‘01‘,0);
133 
134 -- 求各系学生的平均成绩，并把结果存入数据库
135 create table sdept_avg_grade (
136     sdept varchar(20),
137     avg_grade smallint,
138     constraint sag_pk primary key (sdept),
139     constraint s7 check(avg_grade between 0 and 100)
140     -- constraint s8 foreign key (sdept) references student(sdept)  -- 由于外码属性必须为莫关系的主码，此外码定义语句错误
141 );
142 
143 insert into sdept_avg_grade
144 select sdept,avg(grade) from sc,student where sc.sno = student.sno group by sdept ;
145 
146 drop tables sdept_avg_grade;
147 
148 --   将“CS”系全体学生的成绩置零
149 update sc set grade = 0 where ‘CS‘ = (
150 select sdept from student where sc.sno = student.sno);
151 
152 -- 删除“CS”系全体学生的选课记录
153 delete from sc where ‘CS‘ = (
154 select sdept from student where sc.sno = student.sno);
155 
156 -- 删除学号为“13420201”的相关信息(级联删除cascade)
157 delete from student where sno = ‘13420201‘;
158 
159 --  将学号为“13420202”的学生的学号修改为“12420202”（级联更新）
160 update student set sno = ‘12420202‘ where sno = ‘13420202‘;
161 
162 -- 把平均成绩大于80分的男同学的学号和平均成绩存入另一个表S_GRADE（SNO，AVG_GRADE）
163 create table s_grade(
164     sno varchar(8),
165     avg_grade smallint,
166     constraint sg_pk primary key (sno),
167     constraint s9 foreign key (sno) references student(sno),
168     constraint s10 check(grade between 0 and 100)
169 );
170 insert into s_grade
171 select sc.sno,avg(grade) from sc,student where sc.sno = student.sno and ssex = ‘male‘
172 group by sc.sno having avg(grade) > 80;
173 
174 select * from s_grade;
175 drop table s_grade;
176 
177 -- 把选修了课程名为“Data Structures”的学生的成绩提高10%；
178 update sc set grade = grade * 1.1 where ‘Data Structures‘ = (
179 select cname from course where sc.cno = course.cno );
180 
181 select sno,grade from sc,course where sc.cno = course.cno and cname = ‘Data Structures‘;
182 select avg(grade) from sc,course where sc.cno = course.cno and  cname = ‘Data Structures‘;
183 
184 
185 -- ---------------------------------------------------------------------------------------------
186 -- (实验四 数据查询实验)
187 -- ---------------------------------------------------------------------------------------------
188 
189 -- 1．   查询学生的基本信息；
190 select * from student;
191 
192 -- 2．   查询“CS”系学生的基本信息
193 select * from student where sdept = ‘CS‘;
194 
195 -- 3．   查询“CS”系学生年龄不在19到21之间的学生的学号、姓名；
196 select sno,sname from student where sdept = ‘CS‘ and sage not between 19 and 21;
197 
198 -- 4．   找出最大年龄；
199 select max(sage) from student;
200 
201 -- 5．   找出“CS”系年龄最大的学生，显示其学号、姓名；
202 select sno,sname from student where sdept = ‘CS‘ and sage = (
203 select max(sage) from student where sdept = ‘CS‘);
204 
205 -- 6．   找出各系年龄最大的学生，显示其学号、姓名；
206 select sno,sname from student as s1 where sage = (
207 select max(sage) from student as s2 where s1.sdept = s2.sdept);
208 
209 -- 7．   统计“CS”系学生的人数；
210 select count(sno) as number_of_student from student where sdept = ‘CS‘;
211 
212 -- 8．   统计各系学生的人数，结果按升序排列；
213 select sdept, count(sno) as number_of_student from student group by sdept order by number_of_student;
214 
215 -- 9．   按系统计各系学生的平均年龄，结果按降序排列；
216 select sdept,avg(sage) as avg_age from student group by sdept order by avg_age desc;
217 
218 -- 10．  查询每门课程的课程名；
219 select cname from course;
220 
221 -- 11．  查询无先修课的课程的课程名和学分数；注意空值测试语句 ‘is null‘ or ‘is not null‘;
222 select cname,ccredit from course where cpno is null;
223 
224 -- 12．  统计无先修课的课程的学分总数；
225 select sum(ccredit) as total_credit from course where cpno is null;
226 
227 -- 13．  统计每位学生选修课程的门数、学分及其平均成绩；
228 select sc.sno, count(sc.sno) as number_of_course, sum(ccredit) as number_of_credit, avg(grade) as avg_grade
229 from sc, course where sc.cno = course.cno group by sc.sno;
230 
231 -- 14．  统计选修每门课程的学生人数及各门课程的平均成绩；
232 select cno,count(sno) as number_of_student, avg(grade) as avg_grade from sc group by cno;
233 
234 -- 15．  找出平均成绩在85分以上的学生，结果按系分组，并按平均成绩的升序排列；
235 select sc.sno, avg(grade) as avg_grade from sc,student where sc.sno = student.sno
236 group by sc.sno, sdept having avg_grade >= 85 order by avg_grade;
237 
238 -- 16．  查询选修了“01”或“02”号课程的学生学号和姓名；
239 select  distinct sc.sno,sname from sc,student where sc.sno = student.sno and (cno = ‘01‘ or cno = ‘02‘);
240 
241 -- 17．  查询选修了“1”和“2”号课程的学生学号和姓名；
242 select distinct s1.sno,sname from sc as s1,student where s1.sno = student.sno and cno = ‘01‘ and ‘02‘ in (
243 select cno from sc as s2 where s2.sno = s1.sno);
244 
245 select distinct sc.sno,sname from sc,student where sc.sno = student.sno and cno = ‘01‘ and sc.sno in (
246 select sno from sc where cno = ‘02‘);
247 
248 -- 18．  查询选修了课程名为“Database”且成绩在60分以下的学生的学号、姓名和成绩；
249 select sc.sno,sname,grade from sc,student,course where student.sno = sc.sno and sc.cno = course.cno
250 and cname = ‘Database‘ and grade < 60;
251 
252 -- 19．  查询每位学生选修了课程的学生信息（显示：学号，姓名，课程号，课程名，成绩）；
253 select sc.sno,sname,sc.cno,cname,grade from sc,student,course where student.sno = sc.sno
254 and sc.cno = course.cno;
255 
256 -- 20．  查询没有选修课程的学生的基本信息；
257 select sno,sname,sage,ssex,sdept from student where sno not in (select sno from sc);
258 
259 -- 21．  查询选修了3门以上课程的学生学号；
260 select sno from sc group by sno having count(sno) >= 3;
261 
262 -- 22．  查询选修课程成绩至少有一门在80分以上的学生学号；
263 select sno from sc group by sno having max(grade) > 80;
264 
265 -- 23．  查询选修课程成绩均在80分以上的学生学号；
266 select sno from sc group by sno having min(grade) > 80;
267 
268 -- 24．  查询选修课程平均成绩在80分以上的学生学号；
269 select sno from sc group by sno having avg(grade) > 80;
270 
271 -- -----------------------------------------------------
272 drop database s_13420228;