SQL习题1

第一题：
为管理业务培训信息，建立3个表：
S(S#,SN,SD,SA)S#,SN,SD,SA分别代表学号，学员姓名，所属单位，学员年龄
C(C#,CN)C#,CN分别代表课程编号，课程名称
SC(S#,C#,G) S#,C#,G分别代表学号，所选的课程编号，学习成绩
(1)使用标准SQL嵌套语句查询选修课程名称为’税收基础’的学员学号和姓名?
(2) 使用标准SQL嵌套语句查询选修课程编号为’C2’的学员姓名和所属单位?
(3) 使用标准SQL嵌套语句查询不选修课程编号为’C5’的学员姓名和所属单位?
(4) 查询选修了课程的学员人数?
(5) 查询选修课程超过5门的学员学号和所属单位?
drop table S;
drop table C;
drop table SC;
create table S
(
S# varchar(10),
SN varchar (25),
SD varchar (25),
SA int
)
create table C
(
C# varchar(10),
CN varchar (25)
)
create table SC
(
S# varchar(10),
C# varchar(10),
G int
Primary Key(S#, C#)
)
insert into S values ('10001','Students1','department1',23)
insert into S values ('10002','Students2','department1',24)
insert into S values ('10003','Students3','department2',25)
insert into S values ('10004','Students4','department2',26)
insert into S values ('10005','Students5','department3',23)
insert into S values ('10006','Students6','department3',24)
insert into S values ('10007','Students7','department3',25)
insert into S values ('10008','Students8','department4',25)
insert into C values ('C1','数学')
insert into C values ('C2','物理')
insert into C values ('C3','化学')
insert into C values ('C4','英语')
insert into C values ('C5','中文')
insert into C values ('C6','税收基础')
insert into C values ('C7','传媒')
insert into C values ('C8','日语')
insert into SC values ('10001','C1',67)
insert into SC values ('10001','C2',77)
insert into SC values ('10001','C3',87)
insert into SC values ('10001','C4',97)
insert into SC values ('10001','C5',57)
insert into SC values ('10001','C6',47)
insert into SC values ('10002','C1',62)
insert into SC values ('10002','C2',72)
insert into SC values ('10002','C3',82)
insert into SC values ('10002','C4',92)
insert