title: Get an extra comma ',' while using concat
body: <p>I have wrote a stored proc in <code>sqlyog</code>. It is quite long and performing all the desired functionality except for the <em>concat</em> statement so I will only list that particular query.</p>
  
  <pre><code>UPDATE recipes_new 
  SET co_auths = CONCAT(co_auths,',',c1id) 
  WHERE id = name_in; 
  </code></pre>
  
  <p>I basically want a separation in the two fields and this statement is placed in a cursor so it is iterative. <code>co_auths</code> is null at the moment so I get the result as <em>,1,2,3</em> where as I want it to be <em>1,2,3</em>. Any guesses what can the most appropriate solution be?</p>