[Symfony] Propel Criteria Note
When we want to use a sql to get rows between two dates, we can use like this:
$crit1 = $c->getNewCriterion( AppEventPeer::CREATED_AT, $end, Criteria::LESS_THAN );
$crit2 = $c->getNewCriterion( AppEventPeer::CREATED_AT, $start, Criteria::GREATER_THAN );
$crit1->addAnd( $crit2 );
$c->add( $crit1 );
