title: SQL Server : append string not working if col is empty
body: <p>I need to programatically append some string to <code>col1</code>. The below code works only in case <code>col1</code> is not empty. If it's empty then after running the code it remains empty. Why?</p>
  
  <pre><code>UPDATE 
      table
  SET 
      col1 = col1 + ';somestring'
  WHERE 
      col2 = rowID
  </code></pre>