public function listParkedAccounts($days = NULL)
{
    global $db;
    $days_db = (empty($days))?"7":$days;
    $stmt    = "CALL parked_accounts('.$days_db.')";

    $result       = $db->query($stmt,true,'Failed to fetch aged author record');
    $aged_authors = MysqLi_fetch_all($result,MysqLI_ASSOC);
    //MysqL_free_result($result); tried this

    $counter = 0;
    $data    = null;

    foreach($aged_authors as $authors){
        if(empty($authors['call_descp'])){
            $stmt_notes   = "SELECT description From notes WHERE description IS NOT NULL AND parent_id = '".$authors['call_id']."' AND parent_tyPE = 'Calls' ORDER BY date_entered DESC LIMIT 1";
            $notes_descp = $db->getOne($stmt_notes,TRUE,'Error retrieving call notes');


            $notes = (!empty($notes_descp))?$notes_descp[0]['description']:"No Notes";

        }else{
           $notes = (!empty($authors['call_descp']))?$authors['call_descp']:"No Notes";
        }
        $lead = 'stuff';
        $data[$counter]['lead_id']    = $lead;
        $data[$counter]['call_notes'] = $notes;
        $counter++;
    }

    $size = sizeof($data);
    $json_vals['draw'] = "1";
    $json_vals['recordstotal'] = $size;
    $json_vals['recordsFiltered'] = $size;
    $json_vals['data'] = ($size > 0)?$data:array();
    return $json_vals;
}

我的问题是这个错误信息：

我从阅读this中了解到,我需要释放结果或存储它们但是当我尝试这些时我仍然得到相同的错误信息.虽然我不太确定我应该在哪里释放结果,或者我是否正确地执行它们.这是我第一次使用存储过程.