mysql查询

基本查询：

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 between 60 and 80
5、 查询Score表中成绩为85，86或88的记录。
(1)    Seclet * from score where degree=85 or degree=86 or degree=88;
(2)    Select * from score where degree in(85,86,88)
6、 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’;
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 * from student where class=95031;
10、查询Score表中的最高分的学生学号和课程号。（子查询或者排序）
   Select * from score where degree=(select max(degree) from score);
11、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 avg(degree) from score group by cno;
12、查询每门课的平均成绩。
 select avg(degree) from score group by cno;
13、查询分数大于70，小于90的Sno列。
   Select sno from score where degree between 70 and 90;
14、查询所有学生的Sname、Cno和Degree列。
      Select student.sname,score.cno,score.degree from student,score where sno=son;
15、查询所有学生的Sno、Cname和Degree列。
     select student.sno,course.cname,score.degree from student join course join score on student.sno=score.sno and score.cno=course.cno;
16、查询所有学生的Sname、Cname和Degree列。
    Select student.sname,course.cname,score.degree from student,course,score where sno=son;
17、 查询“95033”班学生的平均分
 select avg(degree) from score join student on student.class='95033' and student.sno=score.sno;
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 score where cno='3-105' and degree>(select degree from score where sno='109' and cno='3-105');
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。
 
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 * from score where cno='3-105' and degree>(select degree from score where sno='109' and cno='3-105');
22、查询和学号为107的同学同年出生的所有学生的Sno、Sname和Sbirthday列。
select * from student where sno <> '107' and year(sbirthday) = (select year(sbirthday) from student where sno = '107');
23、查询“张旭“教师任课的学生成绩（姓名）。
select sname,degree from teacher join score join course join student on teacher.tno = course.tno and score.cno=course.cno and score.sno=student.sno where teacher.tname='张旭';
查询考计算机导论的学生成绩
select degree from score join course on course.cno=score.cno and score.cno='3-105';
查询李诚老师教的课程名称
 select cname from course join teacher on course.tno = teacher.tno and teacher.tname='李诚';
教高等数学的老师是哪个系的
select depart from teacher join course on teacher.tno = course.tno and course.cname='高等数学';
24、查询选修某课程的同学人数多于5人的教师姓名。
 
25、查询95033班和95031班全体学生的记录。
select * from student where class='95033' or class='95031';
26、  查询存在有85分以上成绩的课程Cno.
 select cno from score where degree>85;
27、查询出“计算机系“教师所教课程的成绩表。
select degree from course join score on course.cno='3-105' and score.cno='3-105';
29、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 * from score where cno='3-105' and degree>(select min(degree) from score where cno='3-245') order by degree desc;
30、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 * from score where cno='3-105' and degree>(select max(degree) from score where cno='3-245');
31、 查询所有教师和同学的name、sex和birthday.
select tname,tsex,tbirthday from teacher union select sname,ssex,sbirthday from student;
32、查询所有“女”教师和“女”同学的name、sex和birthday.
select tname,tsex,tbirthday from teacher where tsex='女' union select sname,ssex,sbirthday from student where ssex='女';
33、 查询成绩比该课程平均成绩低的同学的成绩表。
select * from 
34、 查询所有任课教师的Tname和Depart.
select tname,depart from teacher;
35、查询所有未讲课的教师的Tname和Depart. 
select tname,depart from teacher where prof='助教';
36、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;
37、查询Student表中不姓“王”的同学记录。
select * from student where not sname like '%王%';
38、查询Student表中每个学生的姓名和年龄。
 
39、查询Student表中最大和最小的Sbirthday日期值。
select min(sbirthday) max,max(sbirthday) min from student;
40、以班号和年龄从大到小的顺序查询Student表中的全部记录。
 
41、查询“男”教师及其所上的课程。
select teacher.tsex,course.cname from teacher join course on teacher.tsex='男' and teacher.tno=course.tno;
42、查询最高分同学的Sno、Cno和Degree列。
select * from score where degree=(select max(degree) from score);
43、查询和“李军”同性别的所有同学的Sname.
select sname from student where ssex='男';
44、查询和“李军”同性别并同班的同学Sname.
select sname from student where ssex='男' and class='95033';
45、查询所有选修“计算机导论”课程的“男”同学的成绩表。
select degree from 

View Code

1.union 合并两个或者多个select语句