get_results("SELECT MAX(tester_email) max_email,MAX(tester_name) max_name,MAX(create_datetime) max_create_datetime,exam_post_id FROM `exam` where exam_post_id=".($_GET['id']+0)." group by tester_email"); echo'

';
foreach($a as$v){
echo implode(',',array($v->max_email,$v->max_name,$v->max_create_datetime,$v->exam_post_id))."
";
}