用PHP脚本来拆分字符串并形成两个新字段

//控制器中
$kindlist = $this->kindgarten->getKindgartenList();
        foreach($kindlist as $key=>$val)
        {
            $arr = explode(",",$val['kgPosition']);
            $updateArr = array(
                'Lng'=>$arr[1],
                'Lat'=>$arr[0]
            );
            $this->kindgarten->addGarten($updateArr , $val['kgId']);
        }

model中

/**
     * @return mixed
     */
    public function getKindgartenList()
    {
        $query = $this->db->get($this->table)->result_array();
        return $query;
    }

    /**
     * 幼儿园数据入库
     * */
    public function addGarten($gartenData,$kgId){

        if(empty($kgId))
        {
            $gartenData['changeTime'] = time().'000';
            $this->db->insert($this->table,$gartenData);
            return $this->db->insert_id();
        }
        else
        {
            return $this->db->update($this->table,$gartenData,array('kgId'=>$kgId));
        }
    }