text: SET client_encoding = 'UTF8';
  DROP SCHEMA IF EXISTS public CASCADE;
  CREATE SCHEMA public;
  
  CREATE TABLE products (
  	product_id serial NOT NULL,
  	title varchar(100) NOT NULL,
  	PRIMARY KEY (product_id)
  );
  
  INSERT INTO products (product_id, title) VALUES
  (1,	'Chair'),
  (2,	'Table'),
  (3,	'Computer');
  SELECT setval('products_product_id_seq', 3, TRUE);
  
  CREATE INDEX title ON products USING btree (title);
  
  CREATE TABLE customers (
  	customer_id serial NOT NULL,
  	name varchar(100) NOT NULL,
  	PRIMARY KEY (customer_id)
  );
  
  INSERT INTO customers (customer_id, name) VALUES
  (1, 'Dave Lister'),
  (2, 'Arnold Rimmer'),
  (3, 'The Cat'),
  (4, 'Holly'),
  (5, 'Kryten'),
  (6, 'Kristine Kochanski');
  SELECT setval('customers_customer_id_seq', 6, TRUE);
  
  CREATE TABLE orders (
  	order_id serial NOT NULL,
  	customer_id integer NOT NULL,
  	product_id integer NOT NULL,
  	amount real NOT NULL
  );
  
  INSERT INTO orders (order_id, customer_id, product_id, amount) VALUES
  (1, 2, 1, 7),
  (2, 2, 3, 2),
  (3, 1, 2, 3),
  (4, 6, 3, 5);
  SELECT setval('orders_order_id_seq', 4, TRUE);
  
  ALTER TABLE ONLY orders
      ADD CONSTRAINT orders_customer_id_fkey FOREIGN KEY (customer_id) REFERENCES customers(customer_id) ON UPDATE CASCADE ON DELETE RESTRICT;
  
  ALTER TABLE ONLY orders
      ADD CONSTRAINT orders_product_id_fkey FOREIGN KEY (product_id) REFERENCES products(product_id) ON UPDATE CASCADE ON DELETE RESTRICT;
  