title: Update values from one column in same table to another in SQL Server
body: <p>I'm trying to overwrite values that are found in TYPE1 with values that are found in TYPE2.</p>
  
  <p>I wrote this SQL to try it out, but for some reason it isn't updating:</p>
  
  <pre><code>select * from stuff
  
  update stuff
  set TYPE1 = TYPE2
  where TYPE1 is null;
  
  update stuff
  set TYPE1 = TYPE2
  where TYPE1 ='Blank';
  </code></pre>
  
  <p><a href="http://www.sqlfiddle.com/#!3/a4733/17" rel="noreferrer">http://www.sqlfiddle.com/#!3/a4733/17</a></p>
  
  <p>Any reason why my values in TYPE1 are not updating?</p>