text: DROP DATABASE IF EXISTS biztime_test;
  
  CREATE DATABASE biztime_test;
  
  \c biztime_test
  
  DROP TABLE IF EXISTS invoices;
  DROP TABLE IF EXISTS companies;
  
  CREATE TABLE companies (
      code text PRIMARY KEY,
      name text NOT NULL UNIQUE,
      description text
  );
  
  CREATE TABLE invoices (
      id serial PRIMARY KEY,
      comp_code text NOT NULL REFERENCES companies ON DELETE CASCADE,
      amt float NOT NULL,
      paid boolean DEFAULT false NOT NULL,
      add_date date DEFAULT CURRENT_DATE NOT NULL,
      paid_date date,
      CONSTRAINT invoices_amt_check CHECK ((amt > (0)::double precision))
  );
  
  INSERT INTO companies
    VALUES ('apple', 'Apple Computer', 'Maker of OSX.'),
           ('ibm', 'IBM', 'Big blue.');
  
  INSERT INTO invoices (comp_Code, amt, paid, paid_date)
    VALUES ('apple', 100, false, null),
           ('apple', 200, false, null),
           ('apple', 300, true, '2018-01-01'),
           ('ibm', 400, false, null);
  