Database lab - create tables

create table department(
dept_name varchar(20) not null,
building varchar(20)  not null,
budget numeric(8,2) not null,
primary key (dept_name)
);

create table instructor(
id char(5),
name varchar(20)  not null,
dept_name varchar(20) not null,
salary numeric(8,0) not null,
primary key (id),
foreign key (dept_name) references department
);

create table student(
id char(5),
name varchar(20)  not null,
dept_name varchar(20) not null,
total_cred numeric(3,0) not null,
primary key (id),
foreign key (dept_name) references department
);

create table student(
id char(5),
name varchar(20)  not null,
dept_name varchar(20) not null,
total_cred numeric(3,0) not null,
primary key (id),
foreign key (dept_name) references department
);


create table course(
course_id varchar(8),
title varchar(50)  not null,
dept_name varchar(20) not null,
credits numeric(2,0) not null,
primary key (course_id),
foreign key (dept_name) references department
);


create table takes(
id char(5),
course_id varchar(8)  not null,
sec_id varchar(8) not null,
semester varchar(6) not null,
year numeric(4,0) not null,
grade varchar(2) not null,
primary key (id,course_id,sec_id,semester,year),
foreign key (id) references student,
foreign key (course_id,sec_id,semester,year) references student,
);

create table advisor(
s_id char(8),
i_id varchar(8),
primary key (s_id),
foreign key (id) references student,
foreign key (id) references instructor
);