• SQL查询语句47题


      1 select * from student
      2 select * from score
      3 --select * from grade
      4 select * from course
      5 select * from teacher
      6 
      7 --1、 查询Student表中的所有记录的Sname、Ssex和Class列。
      8 select sname,ssex,class from Student
      9 --2、 查询教师所有的单位即不重复的Depart列。
     10 select distinct depart from teacher
     11 --3、 查询Student表的所有记录。
     12 select * from student
     13 --4、 查询Score表中成绩在60到80之间的所有记录。
     14 select * from score where degree between 60 and 80
     15 --5、 查询Score表中成绩为85,86或88的记录。
     16 select * from score where degree in (85,86,88)
     17 --6、 查询Student表中“95031”班或性别为“女”的同学记录。
     18 select * from student where class='95031' or ssex=''
     19 --7、 以Class降序查询Student表的所有记录。
     20 select * from student order by class desc
     21 --8、 以Cno升序、Degree降序查询Score表的所有记录。
     22 select * from score order by cno,degree desc
     23 --9、 查询“95031”班的学生人数。
     24 select COUNT(*) from student where class='95031'
     25 --10、查询Score表中的最高分的学生学号和课程号。
     26 select sno,cno from score where degree in (select MAX(degree) from score)
     27 select top 1 sno,cno from score order by degree desc
     28 --11、查询‘3-105’号课程的平均分。
     29 select AVG(degree) from score where cno='3-105'
     30 --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。
     31 select AVG(degree) from score where cno in (select cno from score group by cno having COUNT(*)>=5) and cno like '3%'
     32 select AVG(degree) from score where cno like '3%' group by cno having COUNT(*)>=5
     33 --13、查询最低分大于70,最高分小于90的Sno列。
     34 select distinct sno from score 
     35 where sno in (select sno from score group by sno having MIN(degree)>70) 
     36     and sno in (select sno from score group by sno having MAX(degree)<90)
     37     
     38 select sno from score group by sno having MAX(degree)<90 and MIN(degree)>70
     39 --14、查询所有学生的Sname、Cno和Degree列。
     40 select sname,cno,degree from student,score where student.sno=score.sno
     41 --15、查询所有学生的Sno、Cname和Degree列。
     42 select student.sno,cname,degree from student
     43     join score on student.sno=score.sno
     44     join course on score.cno=course.cno
     45 --16、查询所有学生的Sname、Cname和Degree列。
     46 select sname,cname,degree from student
     47     join score on student.sno=score.sno
     48     join course on score.cno=course.cno
     49 --17、查询“95033”班所选课程的平均分。
     50 select AVG(degree) from score
     51 where degree in (select degree from score join student on student.sno=score.sno where class='95033')
     52 --18、假设使用如下命令建立了一个grade表:
     53 --create table grade(low  int,upp  int,rank  varchar(1))
     54 --insert into grade values(90,100,'A')
     55 --insert into grade values(80,89,'B')
     56 --insert into grade values(70,79,'C')
     57 --insert into grade values(60,69,'D')
     58 --insert into grade values(0,59,'E')
     59 --现查询所有同学的Sno、Cno和rank列。
     60 select sno,cno,[rank] from score,grade where degree between low and upp
     61 --19、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。//无关子查询
     62             --“109”号同学成绩
     63             --select degree from score where sno='109' and cno='3-105'
     64 select * from student join score on student.sno=score.sno 
     65 where cno='3-105' and degree > (select degree from score where sno='109' and cno='3-105')
     66 --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。
     67 --select sno from score group by sno having COUNT(*)>1
     68 --select MAX(degree) from score group by cno
     69 select * from score a 
     70 where sno in (select sno from score group by sno having COUNT(*)>1)
     71 and
     72 (degree not in (select MAX(degree) from score b where a.cno=b.cno group by cno))--相关子查询
     73 
     74 --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。
     75 select * from score where degree>(select degree from score where sno='109' and cno='3-105')
     76 --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。
     77 select sno,sname,sbirthday from student
     78 where YEAR(sbirthday)= YEAR((select sbirthday from student where sno='108'))
     79 --23、查询“张旭“教师任课的学生成绩。
     80 --select cno from course where course.tno=(select tno from teacher where tname='张旭')
     81 select degree from score where cno=(select cno from course where course.tno=(select tno from teacher where tname='张旭'))
     82 --24、查询选修某课程的同学人数多于5人的教师姓名。
     83 --select cno from score group by cno having COUNT(*)>5
     84 --select tno from course where cno=(select cno from score group by cno having COUNT(*)>5)
     85 select tname from teacher 
     86 where tno=(select tno from course where cno=(select cno from score group by cno having COUNT(*)>5))
     87 --25、查询95033班和95031班全体学生的记录。
     88 select student.sno,sname,ssex,sbirthday,class,course.cno,degree,cname,teacher.tno,tname,tsex,prof,depart from student
     89 join score on student.sno=score.sno 
     90 join course on score.cno=course.cno 
     91 join teacher on course.tno=teacher.tno
     92 where class='95033' or class='95031' order by student.sno
     93 --26、查询存在有85分以上成绩的课程Cno.
     94 select distinct cno from score where degree>=85
     95 --27、查询出“计算机系“教师所教课程的成绩表。
     96 --select tno from teacher where depart='计算机系'
     97 --select cno from course where tno in (select tno from teacher where depart='计算机系')
     98 select * from score 
     99 where cno in (select cno from course where tno in (select tno from teacher where depart='计算机系'))
    100 --28、查询“计算机系”与“电子工程系“不同职称的教师的Tname和Prof。//查关子查询 exists存在
    101 select * from teacher t1 where depart='计算机系' and not exists
    102 (
    103     select * from teacher t2 where depart='电子工程系' and t1.prof=t2.prof
    104 )
    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。
    106 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
    107 --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.//相关子查询
    108 --select cno,sno,degree from score where cno='3-105' and degree>(select MAX(degree) from score where cno='3-245')
    109 --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.//相关子查询
    110 select cno,sno,degree from score s1 where  cno='3-105' and sno in
    111 (
    112     select sno from score where cno='3-245'
    113 )
    114  and degree>
    115 (
    116     select degree from score s2 where cno='3-245' and sno in
    117     (
    118         select sno from score where cno ='3-105'
    119     )
    120     and s1.sno=s2.sno
    121 )
    122 --31、查询所有教师和同学的name、sex和birthday.
    123 select sname as name,ssex as sex,sbirthday as birthday from student
    124 union 
    125 select tname,tsex,tbirthday from teacher
    126 --32、查询所有“女”教师和“女”同学的name、sex和birthday.
    127 select sname as name,ssex as sex,sbirthday as birthday from student where ssex=''
    128 union 
    129 select tname,tsex,tbirthday from teacher where tsex=''
    130 --33、查询成绩比该课程平均成绩低的同学的成绩表。
    131 select * from score where degree<(select AVG(degree) from score where cno in (select cno from score group by cno))
    132 
    133 --34、查询所有任课教师的Tname和Depart.
    134 select tname,depart from teacher
    135 --35  查询所有未讲课的教师的Tname和Depart. 
    136 --select cno from course where cno not in (select cno from score)
    137 select tname,depart from teacher 
    138 where tno in (select tno from course where cno= (select cno from course where cno not in (select cno from score)))
    139 
    140 select tname,depart from teacher 
    141 --36、查询至少有2名男生的班号。
    142 select class from student where ssex='' group by class having COUNT(ssex)>=2
    143 --37、查询Student表中不姓“王”的同学记录。
    144 select * from student where sname not like '王%'
    145 --38、查询Student表中每个学生的姓名和年龄。
    146 --(YEAR(GETDATE())-YEAR(sbirthday))
    147 select sname,(YEAR(GETDATE())-YEAR(sbirthday)) from student
    148 --39、查询Student表中最大和最小的Sbirthday日期值。
    149 select MAX(sbirthday),MIN(sbirthday) from student
    150 --40、以班号和年龄从大到小的顺序查询Student表中的全部记录。
    151 select * from student order by class desc,sbirthday
    152 --41、查询“男”教师及其所上的课程。
    153 --select tname from teacher where tsex='男'
    154 --tsex='男' and course.tno in (select tno from teacher where tsex='男')
    155 select tname,cname from teacher 
    156 join course on teacher.tno=course.tno 
    157     where tsex='' and course.tno in (select tno from teacher where tsex='')
    158 --42、查询最高分同学的Sno、Cno和Degree列。
    159 select sno,cno,degree from score where degree in (select MAX(degree) from score)
    160 --43、查询和“李军”同性别的所有同学的Sname.
    161 select sname from student where ssex=(select ssex from student where sname='李军')
    162 --44、查询和“李军”同性别并同班的同学Sname.//也可以用相关子查询
    163 select sname from student where ssex=(select ssex from student where sname='李军') and class=(select class from student where sname='李军')
    164 --45、查询所有选修“计算机导论”课程的“男”同学的成绩表。
    165 select * from score where cno in (select cno from course where cname='计算机导论') and sno in (select sno from student where ssex='')
    166 --46、查询score表中分数最高的学生的信息。//多层嵌套
    167 select * from student where sno in (select sno from score where degree in (select MAX(degree) from score))
    168 --47、查询score表中的平均分在80分以上的学生信息。//无关查询
    169 --select sno from score group by sno having AVG(degree)>=80
    170 select * from student 
    171 where sno in (select sno from score where score.sno in(select sno from score group by sno having AVG(degree)>=80))
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  • 原文地址:https://www.cnblogs.com/zsmj001/p/3963507.html
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