title: Hide columns from SELECT clause conditionally
body: <p>I want to hide columns conditionally from a SELECT clause in a MySQL store procedure. The query is  </p>
  
  <pre><code>SELECT year,gwp_amount,claim_amount,cancellation_amount from tmptable;
  </code></pre>
  
  <p>I want to show <code>gwp_amount,claim_amount,cancellation_amount</code> columns conditionally,</p>
  
  <p>sometimes I want to show <code>gwp_amount and claim_amount</code> columns, </p>
  
  <p>sometimes <code>gwp_amount and cancellation_amount</code> columns, </p>
  
  <p>sometimes <code>one of the column</code> and </p>
  
  <p>sometimes <code>all three columns</code>.</p>
  
  <p>I pass three indicators in store procedure like gwp_ind, calim_ind, cancellation_ind. </p>
  
  <p>I want to show these columns according to these parameters.</p>