更新CodeIgniter中的复选框值

I have an update query problem in CodeIgniter. I am trying to solve that problem but I can't. I have one array $arrpartnerId=([0=>1,[1]=>4,[3]=>5 like..) and my other array is $promotionData['promotion_id']. The inserting into checkbox value is correct, but the updating checkbox value is not working.

My model function is:

  public function update_promotion($promotionData, $partnerData) {
            // print_r( $promotionData['promotion_id']);

            $arrPartnerId = $partnerData['partner_id'];
            print_r($partnerData['partner_id']);



            if (is_array($arrPartnerId) > 0) {
                foreach ($arrPartnerId as $partnerId) {

                    $this->db->set('promotion_id', $promotionData['promotion_id']);
                    $this->db->where('partner_id', $partnerId);
                    $this->db->update('partner_promotion_relation');
                }
            }
        }

If your array is like this,

$arrPartnerId = array(
                     0 => 1,
                     1 => 4,
                     2 => 5
                     );

And

$promotionData['promotion_id'] = 123; //assumption

Then try this,

if(sizeof($arrPartnerId) > 0 )
      {
           foreach( $arrPartnerId as $partnerId)
           {
               $this->db->set('partner_id', $partnerId );
               $this->db->where('promotion_id', $promotionData['promotion_id'] );
               $this->db->update('partner_promotion_relation');
           }
      }

It will resolve the problem.