/*
一个项目涉及到的50个Sql语句
问题及描述：
--1.学生表
Student(S#,Sname,Sage,Ssex) --S# 学生编号,Sname 学生姓名,Sage 出生年月,Ssex 学生性别
--2.课程表 
Course(C#,Cname,T#) --C# --课程编号,Cname 课程名称,T# 教师编号
--3.教师表 
Teacher(T#,Tname) --T# 教师编号,Tname 教师姓名
--4.成绩表 
SC(S#,C#,score) --S# 学生编号,C# 课程编号,score 分数
select * from Student
select * from Course
select * from Teacher
select * from SC
*/
--创建测试数据
create table Student(S# varchar(10),Sname nvarchar(10),Sage datetime,Ssex nvarchar(10))
insert into Student values('01' , N'赵雷' , '1990-01-01' , N'男')
insert into Student values('02' , N'钱电' , '1990-12-21' , N'男')
insert into Student values('03' , N'孙风' , '1990-05-20' , N'男')
insert into Student values('04' , N'李云' , '1990-08-06' , N'男')
insert into Student values('05' , N'周梅' , '1991-12-01' , N'女')
insert into Student values('06' , N'吴兰' , '1992-03-01' , N'女')
insert into Student values('07' , N'郑竹' , '1989-07-01' , N'女')
insert into Student values('08' , N'王菊' , '1990-01-20' , N'女')
create table Course(C# varchar(10),Cname nvarchar(10),T# varchar(10))
insert into Course values('01' , N'语文' , '02')
insert into Course values('02' , N'数学' , '01')
insert into Course values('03' , N'英语' , '03')
create table Teacher(T# varchar(10),Tname nvarchar(10))
insert into Teacher values('01' , N'张三')
insert into Teacher values('02' , N'李四')
insert into Teacher values('03' , N'王五')
create table SC(S# varchar(10),C# varchar(10),score decimal(18,1))
insert into SC values('01' , '01' , 80)
insert into SC values('01' , '02' , 90)
insert into SC values('01' , '03' , 99)
insert into SC values('02' , '01' , 70)
insert into SC values('02' , '02' , 60)
insert into SC values('02' , '03' , 80)
insert into SC values('03' , '01' , 80)
insert into SC values('03' , '02' , 80)
insert into SC values('03' , '03' , 80)
insert into SC values('04' , '01' , 50)
insert into SC values('04' , '02' , 30)
insert into SC values('04' , '03' , 20)
insert into SC values('05' , '01' , 76)
insert into SC values('05' , '02' , 87)
insert into SC values('06' , '01' , 31)
insert into SC values('06' , '03' , 34)
insert into SC values('07' , '02' , 89)
insert into SC values('07' , '03' , 98)
go