title: PostgreSQL command to show entity relations
body: <p>At the start I want to point that I am not and I never was database administrator. I have got experience and knowledge about <code>PL/SQL</code> and <code>SQL</code> but so far each database i get touch with was max 50 tables and looking for relation between entities wasn't that hard even if I made it manually.<br><br> Problem comes now, when I have got <code>database</code> which have over 300 tables finding relation between entities is not so easy. <br> Let imagine table:</p>
  
  <pre><code>table person (
  id serial PRIMARY KEY NOT NULL,
  name varchar(45)
  )
  </code></pre>
  
  <p>and automaticly i have sequence:</p>
  
  <pre><code>person_id_seq
  </code></pre>
  
  <p><br>Can you please tell me if there is any command which return me tables which are using <code>person_id_seq</code>?</p>