phan 4

create table IDThisinhdaduthi (IdKyThi varchar(100), IdThisinhdaduthi varchar(100),  PRIMARY KEY (IdKyThi, IdThisinhdaduthi));
create table Bangtraloicuathisinh (IdBangtraloi varchar(100), IdBaithi varchar(100), Hovatenthisinhtraloi varchar(100),Ngaygiothuchien DATETIME,Thoiluongthuchien TIME,Tongdiembaithi real, IdThisinh varchar(100),   PRIMARY KEY (IdBangtraloi));
create table Luachon (Sothutuluachon varchar(100), IdCauhoi varchar(100), Luachondung varchar(100), Diem real , Vanbanluachon TEXT, PRIMARY KEY (Sothutuluachon, IdCauhoi));
create table Cautraloi (Sothutudaluachon varchar(100), IdCauhoi varchar(100), IdBangtraloi varchar(100),  PRIMARY KEY (IdCauhoi, IdBangtraloi));