Oracle重写sql经典50题（代码）

创建数据库和表

oracle数据库一个账户就一个库不需要创建

学生表 student

创建学生表 student

create table student (
	s_id int,
	s_name varchar(8),
	s_birth date,
	s_sex varchar(4)
);

插入学生数据

注意一条一条执行并提交

insert into Student values(1 , '赵雷' , to_date('1990-01-01','yyyy-MM-dd') , '男');
insert into Student values(2 , '钱电' , to_date('1990-12-21','yyyy-MM-dd') , '男');
insert into Student values(3 , '孙风' , to_date('1990-05-20','yyyy-MM-dd') , '男');
insert into Student values(4 , '李云' , to_date('1990-08-06','yyyy-MM-dd') , '男');
insert into Student values(5 , '周梅' , to_date('1991-12-01','yyyy-MM-dd') , '女');
insert into Student values(6 , '吴兰' , to_date('1992-03-01','yyyy-MM-dd') , '女');
insert into Student values(7 , '郑竹' , to_date('1989-07-01','yyyy-MM-dd') , '女');
insert into Student values(8 , '王菊' , to_date('1990-01-20','yyyy-MM-dd') , '女');

课程表 course

创建课程表 course

create table course (
	c_id int,
	c_name varchar(8),
	t_id int
);

插入课程数据

注意一条一条执行并提交

insert into course values (1,'语文',2);
insert into course values (2,'数学',1);
insert into course values (3,'英语',3);

教师表 teacher

创建教师表 teacher

create table teacher (
	t_id int,
	t_name varchar(8)
);

插入教师数据

注意一条一条执行并提交

insert into teacher values (1,'张三');
insert into teacher values (2,'李四');
insert into teacher values (3,'王五');

成绩表 score

创建成绩表 score

create table score (
	s_id int,
	c_id int,
	s_score int
);

插入成绩数据

注意一条一条执行并提交

insert into score values (1,1,80);
insert into score values (1,2,90);
insert into score values (1,3,99);
insert into score values (2,1,70);
insert into score values (2,2,60);
insert into score values (2,3,65);
insert into score values (3,1,80);
insert into score values (3,2,80);
insert into score values (3,3,80);
insert into score values (4,1,50);
insert into score values (4,2,30);
insert into score values (4,3,40);
insert into score values (5,1,76);
insert into score values (5,2,87);
insert into score values (6,1,31);
insert into score values (6,3,34);
insert into score values (7,2,89);
insert into score values (7,3,98);

经典练习 50 题

1、查询"01"课程比"02"课程成绩高的学生的信息及课程分数

select stu.*,sc0.s_score from student stu inner join (select sc1.* from score sc1 inner join score sc2 on sc1.s_id
 = sc2.s_id and sc1.c_id = 01 and sc2.c_id = 02 where sc1.s_score > sc2.s_score) sc0
    on stu.s_id = sc0.s_id;

2、查询"01"课程比"02"课程成绩低的学生的信息及课程分数

select stu.*,sc0.s_score from student stu inner join (select sc1.* from score sc1 inner join score sc2 on sc1.s_id
 = sc2.s_id and sc1.c_id = 01 and sc2.c_id = 02 where sc1.s_score < sc2.s_score) sc0
    on stu.s_id = sc0.s_id;

3、查询平均成绩大于等于60分的同学的学生编号和学生姓名和平均成绩

select stu.s_id,stu.s_name,avg(sc.s_score) as avgscore
    from score sc left join student stu on sc.s_id = stu.s_id
    group by stu.s_id, stu.s_name having avg(s_score) >= 60 order by s_id;

4、查询平均成绩小于60分的同学的学生编号和学生姓名和平均成绩

select stu.s_id,stu.s_name,avg(sc.s_score) as avgscore
    from score sc left join student stu on sc.s_id = stu.s_id
    group by stu.s_id, stu.s_name having avg(s_score) < 60 order by s_id;

5、查询所有同学的学生编号、学生姓名、选课总数、所有课程的总成绩

select stu.s_id,stu.s_name,count(sc.c_id),nvl(sum(sc.s_score),0) sumscore
from student stu left join score sc on stu.s_id = sc.s_id group by stu.s_id, stu.s_name  order by stu.s_id;

6、查询"李"姓老师的数量

select count(*) 李姓老师的数量 from teacher where t_name like '李%';

7、查询学过"张三"老师授课的同学的信息

select stu.* from student stu
    left join SCORE sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    left join teacher t on c.t_id = t.t_id
where t_name = '张三';

8、查询没学过"张三"老师授课的同学的信息

select stu.* from student stu where stu.s_id not in
(select stu.s_id from student stu
    left join SCORE sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    left join teacher t on c.t_id = t.t_id
where t_name = '张三');

9、查询学过编号为"01"并且也学过编号为"02"的课程的同学的信息

select s.* from score sc1 inner join score sc2 on sc1.s_id = sc2.s_id and sc1.c_id = 01
              and sc2.c_id = 02 left join student s on sc1.s_id = s.s_id;

10、查询学过编号为"01"但是没有学过编号为"02"的课程的同学的信息

select * from student stu where s_id in (select s_id from score where c_id = 01)
and s_id not in (select s_id from score where c_id = 02);

11、查询没有学全所有课程的同学的信息

select stu.* from student stu
    left join score sc on stu.s_id = sc.s_id
    group by stu.s_id,s_name,s_birth,s_sex
    having count(sc.c_id) < (select count(course.c_id) from course)
    order by stu.s_id;

12、查询至少有一门课与学号为"01"的同学所学相同的同学的信息

select distinct stu.* from student stu left join score sc on sc.s_id = stu.s_id
    where sc.c_id in (select c_id from score where s_id = 01) order by stu.s_id;

13、查询和"01"号的同学学习的课程完全相同的其他同学的信息

select * from student inner join (select sc1.s_id from score sc1 inner join (select c_id from score where s_id = 1) s1
    on sc1.c_id = s1.c_id where s_id != 1
    group by sc1.s_id having count(sc1.c_id) = (select count(score.c_id) from score where s_id = 1)) t
    on student.s_id = t.s_id ;

14、查询没学过"张三"老师讲授的任一门课程的学生姓名

select s.* from student s where s.s_id not in (select stu.s_id from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    left join teacher t on c.t_id = t.t_id where t.t_name = '张三');

15、查询两门及其以上不及格课程的同学的学号姓名及其平均成绩

select stu.s_id,stu.s_name,avg(sc.s_score) from student stu
    left join score sc on stu.s_id = sc.s_id where sc.s_score < 60
    group by stu.s_id, stu.s_name having count(sc.c_id) >= 2;

16、检索"01"课程分数小于60按分数降序排列的学生信息

select stu.* from student stu left join score sc on stu.s_id = sc.s_id
where sc.c_id = 01 and sc.s_score < 60 order by sc.s_score desc;

17、按平均成绩从高到低显示所有学生的所有课程的成绩以及平均成绩

select stu.s_name 学生姓名,
        sum(case sc.c_id when 1 then sc.s_score else 0 end ) 语文,
        sum(case sc.c_id when 2 then sc.s_score else 0 end ) 数学,
        sum(case sc.c_id when 3 then sc.s_score else 0 end ) 英语,
        nvl(avg(sc.s_score),0) avgscore
from student stu left join score sc on stu.s_id = sc.s_id
group by stu.s_name order by avgscore desc ;

18、查询各科成绩最高分、最低分和平均分以如下形式显示课程ID课程name最高分最低分平均分及格率中等率优良率优秀率及格为>=60中等为70-80优良为80-90优秀为>=90

select c.c_id 课程ID,c_name 课程name,
       max(sc.s_score) 最高分,min(sc.s_score) 最低分,
       avg(sc.s_score) 平均分,
       sum(case when sc.s_score > 60 then 1 else 0 end ) /count(sc.s_id) 及格率,
       sum(case when sc.s_score between 70 and 80 then 1 else 0 end ) /count(sc.s_id) 中等率,
       sum(case when sc.s_score between 80 and 90 then 1 else 0 end ) /count(sc.s_id) 优良率,
       sum(case when sc.s_score >= 90 then 1 else 0 end ) /count(sc.s_id) 优秀率
from score sc left join course c on sc.c_id = c.c_id group by c.c_id, c_name order by 课程ID;

19、按各科成绩进行排序并显示排名

select stu.s_name,sc.c_id,sc.s_score,rank() over (partition by sc.c_id order by s_score desc) 排名
from score sc left join student stu on sc.s_id = stu.s_id order by sc.c_id,s_score desc ;

20、查询学生的总成绩并进行排名

select stu.s_name,nvl(sum(sc.s_score),0) sumscore from student stu
    left join score sc on stu.s_id = sc.s_id
group by stu.s_name,stu.s_id order by sumscore desc;

21、查询不同老师所教不同课程平均分从高到低显示

select t.t_name,c.c_name,avg(sc.s_score) avgscore from score sc
    left join course c on sc.c_id = c.c_id
    left join teacher t on c.t_id = t.t_id
    group by t.t_name, c.c_name order by avgscore desc ;

22、查询所有课程的成绩第2名到第3名的学生信息及该课程成绩

select * from (select stu.*,sc.c_id,sc.s_score from student stu left join score sc on stu.s_id = sc.s_id
where c_id = 1 order by sc.s_score desc) where ROWNUM <= 2
union select * from (select stu.*,sc.c_id,sc.s_score from student stu left join score sc on stu.s_id = sc.s_id
where c_id = 2 order by sc.s_score desc) where rownum <= 2
union select * from (select stu.*,sc.c_id,sc.s_score from student stu left join score sc on stu.s_id = sc.s_id
where c_id = 3 order by sc.s_score desc) where rownum <= 2 ;

23、统计各科成绩各分数段人数课程编号,课程名称, 100-85 , 85-70 , 70-60 , 0-60 及所占百分比

select sc.c_id 课程编号,c.c_name 课程名称,
       sum(case when s_score between 85 and 100 then 1 else 0 end) "100-85",
       sum(case when s_score between 85 and 100 then 1 else 0 end) /count(sc.s_id)*100 "100-85占比",
       sum(case when s_score between 70 and 85 then 1 else 0 end) "100-85",
       sum(case when s_score between 70 and 85 then 1 else 0 end) /count(sc.s_id)*100 "85-70占比",
       sum(case when s_score between 60 and 70 then 1 else 0 end) "100-85",
       sum(case when s_score between 60 and 70 then 1 else 0 end) /count(sc.s_id)*100 "70-60占比",
       sum(case when s_score between 0 and 60 then 1 else 0 end) "100-85",
       sum(case when s_score between 0 and 60 then 1 else 0 end) /count(sc.s_id)*100 "0-60占比"
       from score sc left join course c on sc.c_id = c.c_id group by sc.c_id, c.c_name order by 课程编号;

24、查询学生平均成绩及其名次

select sc.s_id,stu.s_name,avg(sc.s_score) avgscore,
       rank() over (order by avg(sc.s_score) desc) 排名 from score sc
    left join student stu on sc.s_id = stu.s_id
    group by stu.s_name,sc.s_id order by avgscore desc ;

25、查询各科成绩前三名的记录

select * from (select sc.s_id,stu.s_name,c.c_name,sc.s_score from score sc
    left join student stu on sc.s_id = stu.s_id
    left join course c on sc.c_id = c.c_id where c.c_id = 1
    group by sc.s_id, stu.s_name, c.c_name, sc.s_score order by sc.s_score desc,sc.s_id)
    where rownum <= 3
union all select * from (select sc.s_id,stu.s_name,c.c_name,sc.s_score from score sc
    left join student stu on sc.s_id = stu.s_id
    left join course c on sc.c_id = c.c_id where c.c_id = 2
    group by sc.s_id, stu.s_name, c.c_name, sc.s_score order by sc.s_score desc,sc.s_id)
    where rownum <= 3
union all select * from (select sc.s_id,stu.s_name,c.c_name,sc.s_score from score sc
    left join student stu on sc.s_id = stu.s_id
    left join course c on sc.c_id = c.c_id where c.c_id = 3
    group by sc.s_id, stu.s_name, c.c_name, sc.s_score order by sc.s_score desc,sc.s_id)
    where rownum <=3 ;

26、查询每门课程被选修的学生数

select c.c_name,count(sc.c_id) 学生数 from score sc
    left join course c on sc.c_id = c.c_id group by c.c_name;

27、查询出只有两门课程的全部学生的学号和姓名

select stu.s_id,stu.s_name from score sc
    left join student stu on sc.s_id = stu.s_id
group by stu.s_id, stu.s_name having count(sc.c_id) = 2;

28、查询男生、女生人数

select s_sex,count(*) 人数 from student group by s_sex;

29、查询名字中含有"风"字的学生信息

select * from student where s_name like '%风%';

30、查询同名同性学生名单并统计同名人数

select count(*) 同名同性学生人数 from student stu1
    join student stu2 on stu1.s_id=stu2.s_id and stu1.s_sex = stu2.s_sex
    and stu1.s_id != stu2.s_id;

31、查询1990年出生的学生名单

select * from student where to_char(s_birth,'yyyy-MM-dd') like '%1990%';

32、查询每门课程的平均成绩结果按平均成绩降序排列平均成绩相同时按课程编号升序排列

select sc.c_id,c.c_name, avg(sc.s_score) avgscore from score sc
left join course c on sc.c_id = c.c_id
group by sc.c_id,c.c_name order by avgscore desc ,sc.c_id asc;

33、查询平均成绩大于等于85的所有学生的学号、姓名和平均成绩

select stu.s_id, s_name, avg(sc.s_score) avgscore from student stu
    left join score sc on stu.s_id = sc.s_id
    group by stu.s_id, s_name having avg(sc.s_score) >=85;

34、查询课程名称为"数学"且分数低于60的学生姓名和分数

select stu.s_name,sc.s_score from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    where c_name = '数学' and s_score < 60;

35、查询所有学生的课程及分数情况

select stu.s_id,s_name,
       nvl(sum(case sc.c_id when 1 then sc.s_score end ),0) 语文,
       nvl(sum(case sc.c_id when 2 then sc.s_score end ),0) 数学,
       nvl(sum(case sc.c_id when 3 then sc.s_score end ),0) 英语
    from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    group by stu.s_id, s_name order by s_id;

36、查询任何一门课程成绩在70分以上的姓名、课程名称和分数

select stu.s_name,c.c_name,sc.s_score from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    where s_score > 70;

37、查询课程不及格的学生

select stu.s_name,c.c_name,sc.s_score from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    where s_score < 60;

38、查询课程编号为01且课程成绩在80分以上的学生的学号和姓名

select stu.s_id,stu.s_name from student stu
    left join score sc on stu.s_id = sc.s_id
    where sc.c_id = 1 and sc.s_score >= 80;

39、求每门课程的学生人数

select c.c_name,count(sc.s_id) 学生人数 from score sc
    left join course c on sc.c_id = c.c_id
    group by c.c_name;

40、查询选修"张三"老师所授课程的学生中成绩最高的学生信息及其成绩

select stu.*,select1.maxstu from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    left join
    (select c.c_id,max(s_score) maxstu from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id
    left join teacher t on c.t_id = t.t_id
    where t.t_name = '张三' group by c.c_id) select1 on c.c_id = select1.c_id
    where sc.s_score = select1.maxstu;

41、查询不同课程成绩相同的学生的学生编号、课程编号、学生成绩

Select sc1.s_id,sc1.c_id,sc1.s_score From score sc1 left join
    (select sc.s_score from score sc
group by sc.s_score having count(sc.s_score)>1) b  on sc1.s_score = b.s_score
Where sc1.s_score = b.s_score;

42、查询每门功课成绩最好的前两名

select * from (select stu.s_id,stu.s_name,c.c_name,sc.s_score from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id where sc.c_id = 1
    group by stu.s_id, stu.s_name, c.c_name, sc.s_score
    order by sc.s_score desc,s_id) where rownum <= 2
union all select * from (select stu.s_id,stu.s_name,c.c_name,sc.s_score from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id where sc.c_id = 2
    group by stu.s_id, stu.s_name, c.c_name, sc.s_score
    order by sc.s_score desc,s_id) where rownum <=2
union all select * from (select stu.s_id,stu.s_name,c.c_name,sc.s_score from student stu
    left join score sc on stu.s_id = sc.s_id
    left join course c on sc.c_id = c.c_id where sc.c_id = 3
    group by stu.s_id, stu.s_name, c.c_name, sc.s_score
    order by sc.s_score desc,s_id) where rownum <= 2;

43、统计每门课程的学生选修人数超过5人的课程才统计。要求输出课程号和选修人数查询结果按人数降序排列若人数相同按课程号升序排列

select sc.c_id,count(sc.s_id) 选修人数 from score sc
    group by sc.c_id  having count(sc.s_id) > 5 order by 选修人数 desc ,sc.c_id asc;

44、检索至少选修两门课程的学生学号

select s_id from score group by s_id having count(score.c_id) >= 2 order by s_id;

45、查询选修了全部课程的学生信息

select stu.* from student stu
    left join score sc on stu.s_id = sc.s_id
    group by stu.s_id,s_name,s_birth,s_sex
    having count(sc.c_id) = (select count(*) from course) order by stu.s_id;

46、查询各学生的年龄

select s_name,to_char(sysdate,'yyyy')-to_char(s_birth,'yyyy') 年龄  from student;

47、查询本周过生日的学生

select * from student where to_char(s_birth,'Iw') = to_char(sysdate,'Iw');

48、查询下周过生日的学生

select * from student where to_char(s_birth,'Iw') =to_char(sysdate,'Iw')+ 1;

49、查询本月过生日的学生

select * from student where to_char(s_birth,'MM') = to_char(sysdate,'MM');

50、查询下月过生日的学生

select * from student where to_char(s_birth,'MM') = to_char(sysdate,'MM') + 1;
select * from student;