text: CREATE TABLE users(
      user_id serial PRIMARY KEY,
      name text NOT NULL,
      surname text NOT NULL, 
      avatar text, 
      date_created timestamp NOT NULL,
      is_admin boolean DEFAULT false
      );
  
  CREATE TABLE authors(
      author_id serial PRIMARY KEY,
      user_id integer NOT NULL REFERENCES users ON DELETE CASCADE,
      description text
      );
  
  CREATE TABLE tags(
      tag_id serial PRIMARY KEY,
      name text
      );
  
  CREATE TABLE categories(
      category_id serial PRIMARY KEY,
      name text,
      parent_id integer REFERENCES categories ON DELETE SET NULL
  );
  
  CREATE TABLE news(
      news_id serial PRIMARY KEY,
      title text NOT NULL,
      date_created timestamp NOT NULL,
      author_id integer REFERENCES authors ON DELETE CASCADE,
      category_id integer REFERENCES categories ON DELETE CASCADE,
      content text,
      main_photo text,
      is_draft boolean DEFAULT true
  );
  
  CREATE TABLE tags_news(
      tag_id integer REFERENCES tags ON DELETE CASCADE,
      news_id integer REFERENCES news ON DELETE CASCADE,
      PRIMARY KEY (tag_id, news_id)
  );
  
  CREATE TABLE commentaries(
      commentary_id serial PRIMARY KEY,
      content text NOT NULL,
      news_id integer REFERENCES news
  );
  