title: MySQL/PHP Sort with natural sort
body: <p>I writing a code to get mysql field values sorted.
  my filed values are as below</p>
  
  <pre><code>**downloads**
  N/A
  10
  
  50
  30
  unlimited
  N/A
  70
  unlimited
  </code></pre>
  
  <p>those are on mysql table field.
  i need to sort those assenting and descending like below</p>
  
  <pre><code>Assending
  N/A
  
  10
  30
  50
  70
  unlimited
  unlimited
  
  
  Desending
  unlimited
  unlimited
  70
  50
  30
  10
  
  N/A
  </code></pre>
  
  <p>The space is some rows don't have data. i wrote mysql query like below</p>
  
  <pre><code>SELECT * FROM fltable  ORDER BY LENGTH(downloads), downloads DESC
  </code></pre>
  
  <p>But this not returns correct sort, can anyone help me with this using my sql or php solution.
  Thank You</p>