Echo a comma on all but the last value? (result from mysql_fetch_array)

Question

How do I echo a comma on all but the last value? Here\'s my code:

while ($servdescarrayrow = mysql_fetch_array($servdescarray)) {

    ECHO $servdescarrayrow         


        

Answer 1

$started = null;
while ($servdescarrayrow = mysql_fetch_array($servdescarray)) 
{
  ECHO $started.$servdescarrayrow['serv_desc'];
  if ( ! isset($started))
  {
    $started = ",";
  }
}