title: SQL Stored Procedure: If variable is not null, update statement
body: <p>I have an update statement in a stored procedure that looks generally like this:</p>
  
  <pre><code>Update [TABLE_NAME]
  Set XYZ=@ABC
  </code></pre>
  
  <p>Is there a good way to only trigger the update statement if the variable is not null or the value -1?</p>
  
  <p>Similar to an <code>IF NOT EXISTS...INSERT</code> question.</p>
  
  <p>Thank you so much.</p>