title: Storing string values with four levels of hierarchy
body: <p>The following image shows how my data needs to be stored and linked to each other:</p>
  
  <p><img src="https://i.stack.imgur.com/WYxI9.png" alt=""></p>
  
  <p>The values v1,v2 and so on are all unique. Av1...n and n1....n couple should be the same for different v1...n. Once stored, I need to retrieve it in the following format:</p>
  
  <pre><code>V1,Av1,n1
  V1,Av1.n2
  .
  .
  .
  .
  v4,Av1,n1
  </code></pre>
  
  <p>How do you suggest I do this?</p>