一、设有一数据库，包括四个表：学生表（Student）、课程表（Course）、成绩表（Score）以及教师信息表（Teacher）。
四个表的结构分别如表1-1的表（一）~表（四）所示，数据如表1-2的表（一）~表（四）所示。
用SQL语句创建四个表并完成相关题目。
表结构如下：
表（一）Student (学生use)
表（二）Course（课程表）
表（三）Score(成绩表)
表（四）Teacher(教师表)
二、数据库数据：
表（一）Student (学生use)
表（二）Course（课程表）
表（三）Score(成绩表)
表（四）Teacher(教师表)
建表：
-- 学生表 CREATE TABLE student( sno VARCHAR(20) NOT NULL PRIMARY KEY, sname VARCHAR(20) NOT NULL, ssex VARCHAR(20) NOT NULL, sbirthday DATE, class VARCHAR(20) ) -- 教师表 CREATE TABLE teacher( tno VARCHAR(20) NOT NULL PRIMARY KEY, tname VARCHAR(20) NOT NULL, tsex VARCHAR(20) NOT NULL, tbirthday DATE, prof VARCHAR(20), depart VARCHAR(20) NOT NULL ) -- 课程表 CREATE TABLE course( cno VARCHAR(20) PRIMARY KEY NOT NULL , cname VARCHAR(20) NOT NULL, tno VARCHAR(20) NOT NULL , CONSTRAINT course_teacher_fk FOREIGN KEY(tno) REFERENCES teacher(tno) ) -- 成绩表 CREATE TABLE score( sno VARCHAR(20) NOT NULL, CONSTRAINT score_student_fk FOREIGN KEY(sno) REFERENCES student(sno), cno VARCHAR(20) NOT NULL , CONSTRAINT score_course_fk FOREIGN KEY(cno) REFERENCES course(cno), degree DECIMAL(4,1) ) -- student INSERT INTO student VALUES('108','曾华','男','19770901','95033'); INSERT INTO student VALUES('105','匡明','男','19751002','95031'); INSERT INTO student VALUES('107','王丽','女','19760123','95033'); INSERT INTO student VALUES('101','李军','男','19760220','95033'); INSERT INTO student VALUES('109','王芳','女','19750210','95031'); INSERT INTO student VALUES('103','陆君','男','19740603','95031'); SELECT * FROM student; -- teacher INSERT INTO teacher VALUES('804','李诚','男','19581202','副教授','计算机系'); INSERT INTO teacher VALUES('856','张旭','男','19690312','讲师','电子工程系'); INSERT INTO teacher VALUES('825','王萍','女','19720505','助教','计算机系'); INSERT INTO teacher VALUES('831','刘冰','女','19770814','助教','电子工程系'); SELECT * FROM teacher; -- course INSERT INTO course VALUES('3-105','计算机导论','825'); INSERT INTO course VALUES('3-245','操作系统','804'); INSERT INTO course VALUES('6-166','数字电路','856'); INSERT INTO course VALUES('9-888','高等数学','831'); SELECT * FROM course; -- score INSERT INTO score VALUES('103','3-245',86); INSERT INTO score VALUES('105','3-245',75); INSERT INTO score VALUES('109','3-245',68); INSERT INTO score VALUES('103','3-105',92); INSERT INTO score VALUES('105','3-105',88); INSERT INTO score VALUES('109','3-105',76); INSERT INTO score VALUES('101','3-105',64); INSERT INTO score VALUES('107','3-105',91); INSERT INTO score VALUES('108','3-105',78); INSERT INTO score VALUES('101','6-166',85); INSERT INTO score VALUES('107','6-166',79); INSERT INTO score VALUES('108','6-166',81); SELECT * FROM score; -- 1、查询Student表中的所有记录的Sname、Ssex和Class列。 SELECT sname,ssex,class FROM student; -- 2、查询教师所有的单位即不重复的Depart列。 SELECT DISTINCT depart FROM teacher; -- 3、查询Student表的所有记录。 SELECT * FROM student; -- 4、 查询Score表中成绩在60到80之间的所有记录。 SELECT * FROM score WHERE degree>=60 AND degree<=80; -- 5、查询Score表中成绩为85，86或88的记录。 SELECT * FROM score WHERE degree=85 OR degree=86 OR degree=88; -- 6、查询Student表中“95031”班或性别为“女”的同学记录。 SELECT * FROM student WHERE class=95032 OR ssex='女'; -- 7、以Class降序查询Student表的所有记录。 SELECT * FROM student ORDER BY class DESC; -- 8、以Cno升序、Degree降序查询Score表的所有记录。 SELECT * FROM score ORDER BY cno ASC,degree DESC; -- 9、查询“95031”班的学生人数。 SELECT COUNT(*) FROM student WHERE class=95031; -- 10、查询Score表中的最高分的学生学号和课程号。 SELECT sno,cno FROM score WHERE degree=(SELECT MAX(degree)FROM score); -- 11、 查询每门课的平均成绩。 SELECT cno,AVG(degree)FROM score GROUP BY cno; -- 12、查询Score表中至少有5名学生选修的并以3开头的课程的平均分数。 SELECT cno,AVG(degree)FROM score WHERE cno LIKE '3%' AND cno=(SELECT cno FROM score GROUP BY cno HAVING COUNT(*)>=5); -- 13、查询分数大于70，小于90的Sno列。 SELECT sno FROM score WHERE degree>70 AND degree<90; -- 14、查询所有学生的Sname、Cno和Degree列。 SELECT sname,cno,degree FROM student JOIN score ON student.sno=score.sno; -- 15、查询所有学生的Sno、Cname和Degree列。 SELECT sno,cname,degree FROM course JOIN score ON course.cno=score.cno; -- 16、查询所有学生的Sname、Cname和Degree列。 SELECT sname,cname,degree FROM student JOIN score ON student.sno=score.sno JOIN course ON score.cno=course.cno; -- 17、 查询“95033”班学生的平均分。 SELECT AVG(degree) FROM student JOIN score ON student.sno=score.sno WHERE class='95033'; -- 18、查询选修“3-105”课程的成绩高于“109”号同学成绩的所有同学的记录。 SELECT * FROM student JOIN score ON student.sno=score.sno WHERE cno='3-105' AND degree>(SELECT degree FROM score WHERE cno='3-105' AND sno=109); -- 20、查询score中选学多门课程的同学中分数为非最高分成绩的记录。 SELECT * FROM score a WHERE sno IN(SELECT sno FROM score GROUP BY sno HAVING COUNT(sno)>1) AND degree <> (SELECT MAX(degree)FROM score b WHERE a.cno=b.cno); -- 21、查询成绩高于学号为“109”、课程号为“3-105”的成绩的所有记录。 SELECT degree FROM score WHERE degree>(SELECT degree FROM score WHERE sno=109 AND cno='3-105'); -- 22、查询和学号为108的同学同年出生的所有学生的Sno、Sname和Sbirthday列。 SELECT sno,sname,sbirthday FROM student WHERE sbirthday LIKE CONCAT((SELECT LEFT((SELECT sbirthday FROM student WHERE sno = 108),4)),'%'); -- 23、查询“张旭“教师任课的学生成绩（姓名） SELECT sname,degree FROM student JOIN score ON student.sno=score.sno JOIN course ON score.cno=course.cno WHERE cname=(SELECT cname FROM course JOIN teacher ON course.tno=teacher.tno WHERE tname='张旭'); -- 24、查询考计算机导论的学生成绩 SELECT sname,degree FROM student JOIN score ON student.sno=score.sno JOIN course ON score.cno=course.cno WHERE cname='计算机导论'; -- 25、查询李诚老师教的课程名称 SELECT cname FROM course JOIN teacher ON course.tno = teacher.tno WHERE tname = '李诚'; -- 26、教高等数学的老师是哪个系的 SELECT depart FROM course JOIN teacher ON course.tno = teacher.tno WHERE cname = '高等数学'; -- 27、查询选修某课程的同学人数多于5人的教师姓名。 SELECT tname FROM teacher WHERE tno=(SELECT tno FROM course WHERE cno=(SELECT cno FROM Score GROUP BY cno HAVING COUNT(cno)>5)); -- 28、查询95033班和95031班全体学生的记录。 SELECT * FROM student JOIN score ON student.sno=score.sno JOIN course ON score.cno=course.cno JOIN teacher ON course.tno=teacher.tno WHERE class='95033' OR class='95031'; -- 29、查询存在有85分以上成绩的课程Cno. SELECT cno FROM score WHERE degree>85 -- 30、查询出“计算机系“教师所教课程的成绩表。 SELECT degree FROM score WHERE cno IN(SELECT cno FROM teacher JOIN course ON course.tno=teacher.tno WHERE depart='计算机系') -- 31、查询选修编号为“3-105“课程且成绩至少高于选修编号为“3-245”的同学的Cno、Sno和Degree,并按Degree从高到低次序排序。 SELECT cno,sno,degree FROM score WHERE cno='3-105' AND degree>(SELECT MIN(degree)FROM score WHERE cno='3-245')ORDER BY degree DESC; SELECT cno,sno,degree FROM score WHERE degree>ANY(SELECT degree FROM score WHERE cno='3-245') AND cno='3-105' ORDER BY degree DESC; -- any->表示任意一个 -- all->表示所有 -- 32、查询选修编号为“3-105”且成绩高于选修编号为“3-245”课程的同学的Cno、Sno和Degree. SELECT cno,sno,degree FROM score WHERE cno='3-105' AND degree>(SELECT MAX(degree)FROM score WHERE cno='3-245'); SELECT cno,sno,degree FROM score WHERE degree>ALL(SELECT degree FROM score WHERE cno='3-245') AND cno='3-105' ORDER BY degree DESC; -- 33、查询所有教师和同学的name、sex和birthday. SELECT sname AS'name',ssex AS'sex',sbirthday AS'birthday' FROM student UNION SELECT tname AS'name',tsex AS'sex',tbirthday AS'birthday' FROM teacher; -- 34、查询所有“女”教师和“女”同学的name、sex和birthday. SELECT sname AS'name',ssex AS'sex',sbirthday AS'birthday' FROM student WHERE ssex='女' UNION SELECT tname AS'name',tsex AS'sex',tbirthday AS'birthday' FROM teacher WHERE tsex='女'; -- 35、查询成绩比该课程平均成绩低的同学的成绩表。 SELECT * FROM score a WHERE a.degree<(SELECT AVG(degree) FROM score b WHERE b.cno=a.cno); -- 36、 查询所有任课教师的Tname和Depart. SELECT tname,depart FROM teacher; -- 37、查询所有未讲课的教师的Tname和Depart. SELECT tname,depart FROM teacher WHERE tname NOT IN (SELECT DISTINCT tname FROM teacher,course,score WHERE teacher.tno=course.tno AND course.cno=score.cno); -- 38、查询至少有2名男生的班号 SELECT class FROM student WHERE ssex='男'GROUP BY Class HAVING COUNT(class)>1; -- 39、查询Student表中不姓“王”的同学记录。 SELECT * FROM student WHERE sname NOT LIKE'王%'; -- 40、查询Student表中每个学生的姓名和年龄。 SELECT sname,YEAR(NOW())-YEAR(sbirthday) AS '年龄' FROM student; -- 41、查询Student表中最大和最小的Sbirthday日期值。 SELECT MAX(sbirthday),MIN(sbirthday) FROM student; -- 42、以班号和年龄从大到小的顺序查询Student表中的全部记录。 SELECT * FROM student ORDER BY class DESC,sbirthday ASC; -- 43、查询“男”教师及其所上的课程。 SELECT tname,cname FROM course JOIN teacher ON course.tno = teacher.tno WHERE tsex = '男'; -- 44、查询最高分同学的Sno、Cno和Degree列。 SELECT sno,cno,degree FROM score WHERE degree=(SELECT MAX(degree) FROM score); -- 45、查询和“李军”同性别的所有同学的Sname. SELECT sname FROM student WHERE ssex=(SELECT ssex FROM student WHERE sname='李军') AND sname NOT IN ('李军'); -- 46、查询和“李军”同性别并同班的同学Sname. SELECT sname FROM student WHERE ssex=(SELECT ssex FROM student WHERE sname='李军') AND class=(SELECT class FROM student WHERE sname='李军') AND sname NOT IN ('李军'); -- 47、查询所有选修“计算机导论”课程的“男”同学的成绩表。 SELECT sname,degree FROM student JOIN score ON student.sno=score.sno JOIN course ON score.cno=course.cno WHERE cname='计算机导论' AND ssex='男';