title: How to Retrieve even rows in a table
body: <p>table A</p>
  
  <pre>
  columna   
  ---------
     A
     B            
     C
     :
     :
     Z
  </pre>
  
  <p>Here is how to select even rows. I've written a query like this </p>
  
  <pre class="lang-sql prettyprint-override"><code>select * from (select row_number()over(order by no asc ) as number   
    from number 
   where mod(number,2)=0)as even 
  </code></pre>
  
  <p>It isn't working.</p>