create table student(sno varchar2(10) primary key,sname varchar2(20),sage number(2),ssex varchar2(5));create table teacher(tno varchar2(10) primary key,tname varchar2(20));create table course(cno varchar2(10),cname varchar2(20),tno varchar2(20),constraint pk_course primary key (cno,tno));create table sc(sno varchar2(10),cno varchar2(10),score number(4,2),constraint pk_sc primary key (sno,cno));/*******初始化学生表的数据******/insert into student values (‘s001‘,‘张三‘,23,‘男‘);insert into student values (‘s002‘,‘李四‘,23,‘男‘);insert into student values (‘s003‘,‘吴鹏‘,25,‘男‘);insert into student values (‘s004‘,‘琴沁‘,20,‘女‘);insert into student values (‘s005‘,‘王丽‘,20,‘女‘);insert into student values (‘s006‘,‘李波‘,21,‘男‘);insert into student values (‘s007‘,‘刘玉‘,21,‘男‘);insert into student values (‘s008‘,‘萧蓉‘,21,‘女‘);insert into student values (‘s009‘,‘陈萧晓‘,23,‘女‘);insert into student values (‘s010‘,‘陈美‘,22,‘女‘);commit;/******************初始化教师表***********************/insert into teacher values (‘t001‘, ‘刘阳‘);insert into teacher values (‘t002‘, ‘谌燕‘);insert into teacher values (‘t003‘, ‘胡明星‘);commit;/***************初始化课程表****************************/insert into course values (‘c001‘,‘J2SE‘,‘t002‘);insert into course values (‘c002‘,‘Java Web‘,‘t002‘);insert into course values (‘c003‘,‘SSH‘,‘t001‘);insert into course values (‘c004‘,‘Oracle‘,‘t001‘);insert into course values (‘c005‘,‘SQL SERVER 2005‘,‘t003‘);insert into course values (‘c006‘,‘C#‘,‘t003‘);insert into course values (‘c007‘,‘JavaScript‘,‘t002‘);insert into course values (‘c008‘,‘DIV+CSS‘,‘t001‘);insert into course values (‘c009‘,‘PHP‘,‘t003‘);insert into course values (‘c010‘,‘EJB3.0‘,‘t002‘);commit;/***************初始化成绩表***********************/insert into sc values (‘s001‘,‘c001‘,78.9);insert into sc values (‘s002‘,‘c001‘,80.9);insert into sc values (‘s003‘,‘c001‘,81.9);insert into sc values (‘s004‘,‘c001‘,60.9);insert into sc values (‘s001‘,‘c002‘,82.9);insert into sc values (‘s002‘,‘c002‘,72.9);insert into sc values (‘s003‘,‘c002‘,81.9);insert into sc values (‘s001‘,‘c003‘,‘59‘);commit;select * from teacher;select * from student;select * from course;select * from sc;--1、查询“c001”课程比“c002”课程成绩高的所有学生的学号；SELECT A.SNO FROM (SELECT SNO, SCORE FROM SC WHERE CNO = ‘c001‘) A INNER JOIN (SELECT SNO, SCORE FROM SC WHERE CNO = ‘c002‘) B ON A.SNO = B.SNO WHERE A.SCORE > B.SCORE;--2、查询平均成绩大于60 分的同学的学号和平均成绩；SELECT SNO, AVG(SCORE) FROM SC GROUP BY SNO HAVING AVG(SCORE) > 60;--3、查询所有同学的学号、姓名、选课数、总成绩；SELECT S.SNO, S.SNAME, COUNT(CNO), SUM(SCORE) FROM STUDENT S INNER JOIN SC ON S.SNO = SC.SNO GROUP BY S.SNO, S.SNAME;--4、查询姓“刘”的老师的个数；SELECT COUNT(TNAME) FROM TEACHER WHERE TNAME LIKE ‘刘%‘;--5、查询没学过“谌燕”老师课的同学的学号、姓名；SELECT SNO, SNAME FROM STUDENT WHERE SNO NOT IN (SELECT DISTINCT SNO FROM SC INNER JOIN COURSE C ON SC.CNO = C.CNO INNER JOIN TEACHER T ON C.TNO = T.TNO WHERE TNAME = ‘谌燕‘);SELECT SNO, SNAME FROM STUDENT SS WHERE NOT EXISTS (SELECT 1 FROM (SELECT DISTINCT SNO FROM SC INNER JOIN COURSE C ON SC.CNO = C.CNO INNER JOIN TEACHER T ON C.TNO = T.TNO WHERE TNAME = ‘谌燕‘) TT WHERE SS.SNO = TT.SNO); SELECT SNO, SNAME FROM STUDENT SS WHERE NOT EXISTS (SELECT DISTINCT SNO FROM SC INNER JOIN COURSE C ON SC.CNO = C.CNO INNER JOIN TEACHER T ON C.TNO = T.TNO WHERE TNAME = ‘谌燕‘ AND SS.SNO = SC.SNO);--6、查询学过“c001”并且也学过编号“c002”课程的同学的学号、姓名；SELECT S.SNO, S.SNAME FROM STUDENT S INNER JOIN SC S1 ON S.SNO = S1.SNO WHERE CNO = ‘c001‘ AND EXISTS (SELECT * FROM SC S2 WHERE S1.SNO = S2.SNO AND S2.CNO = ‘c002‘);SELECT S.SNO, S.SNAME FROM STUDENT S INNER JOIN SC S1 ON S.SNO = S1.SNO WHERE CNO = ‘c001‘ AND S1.SNO IN (SELECT S2.SNO FROM SC S2 WHERE S2.CNO = ‘c002‘);SELECT S.SNO, S.SNAME FROM STUDENT S INNER JOIN SC S1 ON S.SNO = S1.SNO WHERE CNO = ‘c001‘ AND EXISTS (SELECT 1 FROM SC S2 WHERE S1.SNO = S2.SNO AND S2.CNO = ‘c002‘);--7、查询学过“谌燕”老师所教的所有课的同学的学号、姓名；SELECT DISTINCT S.SNO, S.SNAME FROM STUDENT S INNER JOIN SC ON S.SNO = SC.SNO INNER JOIN COURSE C ON SC.CNO = C.CNO INNER JOIN TEACHER T ON C.TNO = T.TNO WHERE T.TNAME = ‘谌燕‘ ORDER BY SNO;SELECT S.SNO, S.SNAME FROM STUDENT S WHERE EXISTS (SELECT SNO FROM SC INNER JOIN COURSE C ON SC.CNO = C.CNO INNER JOIN TEACHER T ON C.TNO = T.TNO WHERE T.TNAME = ‘谌燕‘ AND S.SNO = SC.SNO);SELECT S.SNO, S.SNAME FROM STUDENT S WHERE SNO IN (SELECT SNO FROM SC INNER JOIN COURSE C ON SC.CNO = C.CNO INNER JOIN TEACHER T ON C.TNO = T.TNO WHERE T.TNAME = ‘谌燕‘);--8、查询课程编号“c002”的成绩比课程编号“c001”课程低的所有同学的学号、姓名；SELECT S1.SNO FROM SC S1 WHERE S1.CNO = ‘c001‘ AND EXISTS (SELECT * FROM SC S2 WHERE S1.SNO = S2.SNO AND S2.CNO = ‘c002‘ AND S1.SCORE > S2.SCORE);SELECT S.SNO, S.SNAME FROM STUDENT S INNER JOIN SC S1 ON S.SNO = S1.SNO AND S1.CNO = ‘c001‘ AND EXISTS (SELECT * FROM SC S2 WHERE S1.SNO = S2.SNO AND S2.CNO = ‘c002‘ AND S1.SCORE > S2.SCORE);---------------------------------------SELECT S.SNO, S.SNAME FROM STUDENT S INNER JOIN (SELECT SNO, SCORE FROM SC WHERE CNO = ‘c001‘) A ON S.SNO = A.SNO INNER JOIN (SELECT SNO, SCORE FROM SC WHERE CNO = ‘c002‘) B ON A.SNO = B.SNO WHERE A.SCORE > B.SCORE; --9、查询所有课程成绩小于60 分的同学的学号、姓名；SELECT S.SNO, S.SNAME FROM STUDENT S WHERE SNO NOT IN (SELECT SNO FROM SC WHERE SCORE > 60);SELECT S.SNO, S.SNAME FROM STUDENT S WHERE NOT EXISTS (SELECT SNO FROM SC WHERE SCORE > 60 AND SC.SNO = S.SNO);--10、查询没有学全所有课的同学的学号、姓名；--11、查询至少有一门课与学号为“s001”的同学所学相同的同学的学号和姓名；--12、查询至少学过学号为“s001”同学所有一门课的其他同学学号和姓名；--13、把“SC”表中“谌燕”老师教的课的成绩都更改为此课程的平均成绩；--14、查询和“s001”号的同学学习的课程完全相同的其他同学学号和姓名；--15、删除学习“谌燕”老师课的SC 表记录；--16、向SC 表中插入一些记录，这些记录要求符合以下条件：没有上过编号“c002”课程的同学学号、“c002”号课的平均成绩；--17、查询各科成绩最高和最低的分：以如下形式显示：课程ID，最高分，最低分--18、按各科平均成绩从低到高和及格率的百分数从高到低顺序--19、查询不同老师所教不同课程平均分从高到低显示--21、查询各科成绩前三名的记录:(不考虑成绩并列情况)--22、查询每门课程被选修的学生数--23、查询出只选修了一门课程的全部学生的学号和姓名--24、查询男生、女生人数--25、查询姓“张”的学生名单--26、查询同名同性学生名单，并统计同名人数--27、1981 年出生的学生名单(注：Student 表中Sage 列的类型是number)--28、查询每门课程的平均成绩，结果按平均成绩升序排列，平均成绩相同时，按课程号降序排列--29、查询平均成绩大于85 的所有学生的学号、姓名和平均成绩--30、查询课程名称为“数据库”，且分数低于60 的学生姓名和分数------------------------------------------------------------------------------------------------------------------31、查询所有学生的选课情况；--32、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；--33、查询不及格的课程，并按课程号从大到小排列--34、查询课程编号为c001 且课程成绩在80 分以上的学生的学号和姓名；--35、求选了课程的学生人数--36、查询选修“谌燕”老师所授课程的学生中，成绩最高的学生姓名及其成绩--37、查询各个课程及相应的选修人数--38、查询不同课程成绩相同的学生的学号、课程号、学生成绩--39、查询每门功课成绩最好的前两名--40、统计每门课程的学生选修人数（超过10 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--41、检索至少选修两门课程的学生学号--42、查询全部学生都选修的课程的课程号和课程名--43、查询没学过“谌燕”老师讲授的任一门课程的学生姓名--44、查询两门以上不及格课程的同学的学号及其平均成绩--45、检索“c004”课程分数小于60，按分数降序排列的同学学号--46、删除“s002”同学的“c001”课程的成绩-- -- --