title: WHERE vs HAVING
body: <p>Why do you need to place columns you create yourself (for example <code>select 1 as "number"</code>) after <code>HAVING</code> and not <code>WHERE</code> in MySQL?</p>
  
  <p>And are there any downsides instead of doing <code>WHERE 1</code> (writing the whole definition instead of a column name)?</p>