title: sql server select performance guid vs string
body: <p><strong>This is not about PKs!</strong></p>
  
  <p>I wonder which will be faster on select:</p>
  
  <pre><code>select * from stuff where someguidcol = '83ce47d2-ac4c-488a-863c-c5f31e8f87aa'
  </code></pre>
  
  <p>or this one </p>
  
  <pre><code>select * from stuff where somestrcol = 'DS3DvDVIPEG1X8Ui7U84DA'
  </code></pre>
  
  <p><em>somestrcol datatype will be char(22)</em></p>
  
  <p><em>Non-clustered indexes will be applied, probably...</em></p>