text: DROP TABLE IF EXISTS transmission CASCADE;
  DROP TABLE IF EXISTS engine CASCADE;
  DROP TABLE IF EXISTS body CASCADE;
  DROP TABLE IF EXISTS car CASCADE;
  
  CREATE TABLE transmission (
  	id serial primary key,
  	type varchar(50) NOT NULL
  );
  
  CREATE TABLE engine (
  	id serial primary key,
  	type varchar(50) NOT NULL
  );
  
  CREATE TABLE body (
  	id serial primary key,
  	type varchar(50) NOT NULL
  );
  
  CREATE TABLE car (
  	id serial primary key,
  	name varchar(50) NOT NULL,
  	transmission integer references transmission(id) NOT NULL,
  	engine integer references engine(id) NOT NULL,
  	body integer references body(id) NOT NULL
  );
  