EF基础知识小记四(数据库=>模型设计器)

--建表脚本
create table Student
(
    Id int not null,
    Name varchar(30) not null,
    Age int not null
)
create table Teacher
(
    Id int not null,
    Name varchar(30) not null,
    Age int not null
)

create table StudentTeacher
(
    StudentId int not null,
    TeacherId int not null
)

create table InfoCard
(
    Id int not null,
    [Money] int not null,
    StudentId int not null
)

--给表添加约束
--单主键约束
alter table Student add constraint [PK_People]
primary key clustered (Id Asc)

alter table InfoCard add constraint [PK_InfoCard]
primary key clustered (Id Asc)

alter table Teacher add constraint [PK_Teacher]
primary key clustered (Id Asc)

--双主键约束(多对多)
alter table StudentTeacher add constraint [PK_StudentTeacher]
primary key clustered (StudentId,TeacherId Asc)

--双外键约束(多对多)
alter table StudentTeacher
add constraint [FK_StudentTeacher_Student]
foreign key (StudentId) references Student (Id) on delete no action on update no action --级联更新级联删除

alter table StudentTeacher add constraint [FK_StudentTeacher_Teacher]
foreign key (TeacherId) references Teacher (Id) on delete no action on update no action 

--但外键约束(一对多)
alter table InfoCard add constraint [FK_InfoCard_Student]
foreign key (StudentId) references Student (Id) on delete no action on update no action