create database PC_1;
use PC_1;
create table pc(code int primary key, model varchar(4), speed decimal(4, 0) not null, hd decimal(3,0) not null, cd varchar(3) not null,
price float);
create table laptop(code int primary key, model varchar(4), speed decimal(4,0) not null, d decimal(3,0) not null, cd varchar(3) not null,
price float);
create table printer(code int primary key, model varchar(4), color char(1), type varchar(6) not null, price float not null);
create table product(maker char(1) not null, model varchar(4) primary key, type varchar(7) not null);