...谢谢了 如下三个表格。根据下面的建立 要代码就好了 万分感谢!_百度...

发布网友 发布时间：2024-10-05 10:38

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热心网友 时间：2024-10-22 11:27

create table Department
(
departId char(2) not null primary key ,
departName varchar(30) not null
)
create table Speciality
(
specId char(4) not null primary key ,
specName varchar(30) not null ,
departId char(2) null ,
foreign key(departId) references Department(departId)
)
create table Class
(
classId char(8) not null primary key ,
className varchar(30) null ,
specId char(4) null ,
departId char(2) null ,
remark varchar(30) null ,
foreign key(specId) references Speciality(specId) ,
foreign key(departId) references Department(departId)
)

热心网友 时间：2024-10-22 11:34

create table Department
(
departId char(2) not null primary key ,
departName varchar(30) not null
)
create table Speciality
(
specId char(4) not null primary key ,
specName varchar(30) not null ,
departId char(2) null ,
foreign key(departId) references Department(departId)
)
create table Class
(
classId char(8) not null primary key ,
className varchar(30) null ,
specId char(4) null ,
departId char(2) null ,
remark varchar(30) null ,
foreign key(specId) references Speciality(specId) ,
foreign key(departId) references Department(departId)
)