title: SELECT TableName.Col1 VS SELECT Col1
body: <p>This might be a weird question but didnt know how to research on it. When doing the following query:</p>
  
  <pre><code>  SELECT Foo.col1, Foo.col2, Foo.col3
    FROM Foo
    INNER JOIN Bar ON Foo.ID = Bar.BID
  </code></pre>
  
  <p>I tend to use <code>TableName.Column</code> instead of just <code>col1, col2, col3</code></p>
  
  <p>Is there any performance difference? Is it faster to specify Table name for each column?</p>
  
  <p>My guess would be that yes it is faster since it would take some time to lookup the column name and and differentiate it. </p>
  
  <p>If anyone knows a link where I could read up on this I would be grateful. I did not even know how to title this question better since not sure how to search on it.</p>