我有这个sql查询，它看起来很混乱，我想知道如何将它转换为codeigniter活动记录查询。
我曾考虑过这样的循环：

for ( $i=1 ; $i<=5 ; $i++) {
     ${'line'.$i} = $this->staffrequisition_model->getRequestsToProcess($i,$staffInfo->position_depth,$staffInfo->department_group);
}
$data = array_merge($line1, $line2, $line3, $line4, $line5);

在我的模型中使用此方法

public function getRequestsToProcess($i,$depth,$departmentGroup)
{
    $this->db->select('*, ns_request_info.idx as request_idx, ns_staff_info.idx as staff_idx');    
    $this->db->from('ns_request_info');
    $this->db->join('ns_staff_info', 'ns_request_info.requested_by_idx = ns_staff_info.member_idx');
    $this->db->where('line'.$i.'', $depth);
    $this->db->where('line'.$i.'_action', 'PENDING');
    if($departmentGroup!='HIGHER TIER'){ $this->db->where('ns_staff_info.department_group', $departmentGroup); }
    $this->db->where('status', 'PENDING');
    $this->db->or_where('status', 'ONGOING');
    $this->db->where('line'.$i.'', $depth);
    $this->db->where('line'.$i.'_action', 'PENDING');
    if($departmentGroup!='HIGHER TIER'){ $this->db->where('ns_staff_info.department_group', $departmentGroup); }
    $this->db->order_by('idx', 'desc');
    $query = $this->db->get();
    return $query->result_array();
}

但我意识到，对所有这些元素进行数组合并会破坏结果的id排序。
这里有我的sql查询，我不知道如何将其转换为codeigniter活动记录查询。

SELECT *, ns_request_info.idx as request_idx, ns_staff_info.idx as staff_idx 

FROM `ns_request_info` 
INNER JOIN `ns_staff_info` 
ON ns_request_info.requested_by_idx = ns_staff_info.member_idx 

WHERE (
    (ns_request_info.line1=1 AND ns_request_info.line1_action='PENDING') OR
 (ns_request_info.line2=1 AND ns_request_info.line2_action='PENDING') OR
 (ns_request_info.line3=1 AND ns_request_info.line3_action='PENDING') OR
 (ns_request_info.line4=1 AND ns_request_info.line4_action='PENDING') OR
 (ns_request_info.line5=1 AND ns_request_info.line5_action='PENDING')
    ) AND (ns_request_info.status='PENDING' OR ns_request_info.status='ONGOING') 
ORDER BY ns_request_info.idx DESC

我希望你们能帮我。