practice sql

create table meeting_room(
rLevel int,
rNumber int,
rSize int not null check (rSize>0),
constraint roompk primary key (rLevel,rNumber)
);

create table meeting_booking(
ID char(4),
date date not null,
purpose varchar(30) not null,
rLevel2 int,
rNumber2 int,
constraint bookingpk primary key (ID),
constraint booking fk foreign key (rLevel2, rNumber2) reference meeting_room (rLevel, rNumber)
);