title: SQL subbstr Negative starting position
body: <p>Can someone please explain what the below piece of code is executing?</p>
  
  <p>I know it is using the length of the symbol field as the number of characters to take. However, the negative 2 is confusing me. So, I'm not sure what it is executing. </p>
  
  <pre><code>substr(symbol,-2,length(symbol)) 
  </code></pre>
  
  <p>Thanks in advance.</p>