title: MySQL case makes a new column
body: <p>If I use a MySQL case statement, it creates a new column, it didn't replace the column.</p>
  
  <p>Is it possible to replace the column instead of new column?</p>
  
  <p>Example:</p>
  
  <pre><code>SELECT *, 
         CASE WHEN housenumber_addition IS NULL THEN 'ABC' 
         ELSE housenumber_addition END AS housenumber_addition 
  FROM customer
  </code></pre>