.1 查询每门课程成绩都大于80分学生的学号
数据库 表 student
name score course
A 85
A 75
A 82
B
B
B
天使美眉90 语文
天使美眉100 数学
天使美眉100 英语
请找出每门课程都超过80分的那个人名字的SQL语句
SQL1:
select name from
group by name
having count(score) =sum(case
SQL2:
select name from stu
group by name
having name not in (
select name from stu
where score <80)
SQL3:
select name from
group by name
having min(score)>=80
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2. 查询课程001的成绩大于课程002成绩的学号
student表:sno(学号),sname(姓名),sex(性别),dept(系)
course课程表:cno(课程号),课程名(cname)
sc选课表:sno,cno,grade(成绩)
select cno from sc a inner join (select * from sc where cno=(select cno from course where cname='001')) as b on >o=(select cno from course where cname='002')
================================================
3、关于group by表内容:
2005-05-09 胜
2005-05-09 胜
2005-05-09 负
2005-05-09 负
2005-05-10 胜
2005-05-10 负
2005-05-10 负
如果要生成下列结果, 该如何写sql语句
2005-05-09
2005-05-10
--------------------------------------------------------
1) select rq,sum(case when shengfu='胜' then 1 else 0 end) as胜,sum(case when shengfu='负' then 1 else 0 end) as负from tab3 group by rq
2) select ,N. 胜,M. 负 from
(select rq,count(*) 胜 from tab3 where shengfu='胜'group by rq)N inner join
(select rq,count(*) 负from tab3 where shengfu='负'group by rq)M on =
3) select ,a. 胜
(select rq,count(shengfu) 胜from tab3 where shengfu='胜' group by rq) a,
(select rq,count(shengfu) 负from tab3 where shengfu='负' group by rq) b
where =;
4)select time, sum(decode(status,'胜','')) 胜 ,sum(decode(status,'负','')) 负 from shengfu_table group by time;
======================================================
4.表中有A B C三列,用SQL语句实现:当A列大于B列时选择A列否则选择B列,当B列大于C列时选择B列否则选择C列。
select (case when a>b then a else b end),(case when b>c then b else c end) from tab4
5.一个日期判断的sql语句请取出tab5表中日期(SendTime字段)为当天的所有记录 (SendTime字段为datetime型,包含日期与时间)
select * from tab5 t where to_char(,'yyyy-mm-dd')=to_char(sysdate,'yyyy-mm-dd')
6.有一张表,里面有3个字段:语文,数学,英语。其中有3条记录分别表示语文70分,数学80分,英语58分,请用一条sql语句查询出这三条记录并按以下条件显示出来(并写出您的思路):
-------------------------------------------------------
select
(case when语文>=80 then '优秀' when语文>60 then '及格' else '不及格' end) as 语文,
(case when 数学>=80 then '优秀' when数学>60 then '及格' else '不及格' end) as数学,
(case when英语>=80 then '优秀' when英语>60 then '及格' else '不及格' end) as 英语
from tab5
==================================
7.请用一个sql语句得出结果
从table1,table2中取出如table3所列格式数据
table1
月份mon
-------------------------------
一月份
一月份
一月份
二月份
二月份
三月份
table2
部门dep
--------------------------------
table3 (result)
部门dep
---------------------------------------------------
-------------------------------------------------------
1)
select ,
(select yj from tab6 where mon='一月份' and dep=) 一月份,
(select yj from tab6 where mon='二月份' and dep=) 二月份,
(select yj from tab6 where mon='三月份' and dep=) 三月份
from tab7 t
---------------------
2)求总销售额
select
sum(case when ='一月份' then else 0 end) 一月份,
sum(case when ='二月份' then else 0 end) 二月份,
sum(case when ='三月份' then else 0 end) 三月份
from tab7 t,tab6 t1 where =
8.一个表中的Id有多个记录,把所有这个id的记录查出来,并显示共有多少条记录数。
-------------------------------------------
select id,count(*) from tab8 group by id having count(*)>1
select * from (select tab8,count(id) as num from tab8 group by id) t where >1
9.用一条SQL语句 查询出每门课都大于80分的学生姓名
8.一个叫department的表,里面只有一个字段name,一共有4条纪录,分别是a,b,c,d,对应四个球对,现在四个球对进行比赛,用一条sql语句显示所有可能的比赛组合.
select ||'vs'|| from tab10 t,tab10 t1 where $amp;
select ||'vs'|| from tab10 t,tab10 t1 where $amp;这个是不分的
=================================
10.怎么把这样一个表儿
year
1991
1991
1991
1991
1992
1992
1992
1992
查成这样一个结果
year m1
1991 1.1 1.2 1.3 1.4
1992 2.1 2.2 2.3 2.4
a):
select ,
(select from tab11 a where =1 and =) m1,
(select from tab11 b where =2 and =) m2,
(select from tab11 c where =3 and =) m3,
(select from tab11 d where =4 and =) m4
from tab11 t group by
11.拷贝表(拷贝数据,源表名:a 目标表名:b)
SQL: insert into b(a, b, c) select d,e,f from b;
create table test as select * from dept; --从已知表复制数据和结构
create table test as select * from dept where 1=2; --从已知表复制结构但不包括数据
12.显示文章、提交人和最后回复时间
13.日程安排提前五分钟提醒
14.两张关联表,删除主表中已经在副表中没有的信息
15.有两个表tab12和tab13,均有key和value两个字段,如果tab13的key在tab12中也有,就把tab13的value换为tab12中对应的value
update tab13 set value=(select value from tab12 where =)
16.原表:
courseid coursename score
-------------------------------------
-------------------------------------
为了便于阅读,查询此表后的结果显式如下(及格分数为60):
courseid coursename score mark
---------------------------------------------------
---------------------------------------------------
select ,,,(case when score>60 then 'pass' else 'fail' end) mark from tab14 t
17.表15
a1
1
1
2
2
2
用select能选成以下结果吗?
1 ab
2 xyz
SELECT a1, replace(max(sys_connect_by_path(a2, ' ')),' ','') NAME
START WITH rn1 IS NULL
CONNECT BY rn1 = PRIOR rn
GROUP BY a1;
18.题为
有两个表, t1, t2,
Table t1:
SELLER | NON_SELLER
-----
Table t2:
SELLER |
------
要求用SELECT 语句列出如下结果:------如A的SUM(BAL)为B,C,D的和,B的SUM(BAL)为A,C,D的和.......
且用的方法不要增加数据库负担,如用临时表等
SELECT SELLER, FROM t,(SELECT SUM(BAL) total FROM t)a;
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