create table system.Book(
Bid varchar(40) primary key,
Bname varchar(50),
Bprice int,
Bnum int,
Bpublish varchar(50),
Bdate varchar(50)
);

create table system.GetBInfo(
Rid varchar(40) not null,
Bid varchar(40) not null,
Getdate varchar(50) not null,
Setdate varchar(50) not null,
constraint c_form foreign key(Rid) references system.Reader(Rid),
constraint c_form1 foreign key(Bid) references system.Book(Bid)
);

 create table system.ReaderType(
 Typeid varchar(40) primary key,
 Typename varchar(50),
 Getmaxnum int not null,
 Getmaxday int not null
 );

create table system.YhInfo(
yhbh varchar(40) primary key,
userN varchar(50),
password varchar(40)
);

create table system.Reader(
Rid varchar(40) primary key,
Rname varchar(50),
Rtypeno varchar(40),
Rgetnum int not null,
constraint c_vv foreign key(Rtypeno) references system.ReaderType(Typeid)
);