MySQL查询语句练习集合

没有数据库先执行50q数据库

查询student表中的所有记录的sname,ssex,class列
select SNAME,SSEX,CLASS from student;
查询教师所有的单位即不重复的Depart列
select distinct DEPART from teacher;
查询Student表的所有记录
select * from student;
查询Score表中成绩在60到80之间的所有记录
select * from score where degree between 60 and 80;
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;
查询Student表中“95031”班或性别为“女”的同学记录
select * from student where class='95031' and ssex='女';
以Class降序查询Student表的所有记录
select * from student order by class desc;
以Cno升序、Degree降序查询Score表的所有记录
select * from score order by degree desc , cno;
查询“95031”班的学生人数
select count(*) as '人数' from student where class='95031';
查询Score表中的最高分的学生学号和课程号
select * from score order by degree desc limit 1;
查询‘3-105’号课程的平均分
select avg(degree) from score where CNO='3-105';
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%' group by cno having count(sno)>5;
查询最低分大于70，最高分小于90的Sno列
select sno from score group by sno having min(degree)>70 and max(degree)<90;
查询所有学生的Sname、Cno和Degree列.
Select sname,cno ,degree from student inner join score on student.sno=scire.sno;
查询“95033”班所选课程的平均分
Select cno,avg(degree) as avg from score where sno in(select sno from student where class=’95033’)group by cno;
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 degree from score where sno=’109’ and cno=’3-105’;
查询score中选学一门以上课程的同学中分数为非最高分成绩的记录
Select sno from score group by sno having count(*)>1;
Select * from score where sno in (Select sno from score group by sno having count(*)>1)
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;
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' unio
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 * from score where DEGREE>(select DEGREE from score where sno='109'and CNO='3-105');
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 year(sbirthday)=(select year(sbirthday) from student where sno=108);
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 year(sbirthday)=(select year(sbirthday) from student where sno=108);
查询Student表中不姓“王”的同学记录
Select * from student where sname not like '王%'
查询“张旭“教师任课的学生成绩
Select degree from score,teacher,course where score.cno=course.cno and course.tno=teacher.tno and teacher.tname='张旭';
查询选修某课程的同学人数多于5人的教师姓名
Select cno from score group by cno having count(*)>5;
Select tname from teacher as t inner join course as c
On t.tno=c.tno where cno in(Select cno from score group by cno having count(*)>5);
查询95033班和95031班全体学生的记录
select * from student where class='95033' or '95031';
查询出“计算机系“教师所教课程的成绩表
Select score.*from teacher as inner join course as con t.tno=c.cno inner join score as con c,cno=s.scno
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 degree from score where cno=’3-105’
And degree>all(Select degree from score where cno=’3-245’)
查询所有姓李的同学的sno,sname,cno,degree
Select s.sno,sname,cno,degree from student as s inner join score as c no s.sno=c.sno where sname like ‘李%’;
查询成绩比该课程平均成绩低的同学的成绩表
Select * from score where degree<(select avg (degree)from score as s where cno=s.cno);
查询所有任课教师的Tname和Depart
select tname,depart from teacher where tno in (select tno from course where cno in (select distinct cno from score));
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);
查询至少有2名男生的班号
select class from student where ssex='男' group by class having count(*)>1;
查询“男”教师及其所上的课程
select tname,cname from teacher ,course where tsex='男' and teacher.tno=course .tno;
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 sname not in ('李军') and class =(select class from student where sname='李军');

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