text: CREATE TABLE IF NOT EXISTS users (
      id SERIAL PRIMARY KEY,
      username VARCHAR(255) UNIQUE NOT NULL,
      password VARCHAR(255) NOT NULL,
      email VARCHAR(255) UNIQUE NULL,
      firstname VARCHAR(100) NULL,
      surname VARCHAR(100) NULL,
      avatar VARCHAR(100) NULL,
      active INT NOT NULL
  );
  
  CREATE TABLE IF NOT EXISTS roles
  (
      id SERIAL PRIMARY KEY,
      name VARCHAR(100) NOT NULL,
      active INT NOT NULL
  );
  
  CREATE TABLE IF NOT EXISTS users_roles
  (
      users_id INT NOT NULL,
      roles INT NOT NULL,
      FOREIGN KEY (users_id) REFERENCES users (id)
  );
  