title: how to find the highest normal form for a given relation
body: <p>I've gone through internet and books and still have some difficulties on how to determine the normal form of this relation</p>
  
  <pre><code>R(a, b, c, d, e, f, g, h, i)
  FDs =
  B→G
  BI→CD
  EH→AG
  G→DE
  </code></pre>
  
  <p>So far I've got that the only candidate key is BHI (If I should count with F, then BFHI).
  Since the attribute F is not in use at all. Totally independent from the given FDs. </p>
  
  <ol>
  <li>What am I supposed to do with the attribute F then?</li>
  <li>How to determine the highest normal form for the realation R?</li>
  </ol>