codeigniter 操作mysql的PHP代码--更新

$this->db->get_where('host',array('host'=>'ddd','id !='=>0))->row();

return $this->db
->select('f.*,count(s.id) as subtotal')
->from('category as f')->join('category s', 'f.id=s.upid', 'left')
->where('f.upid', $upid)
->group_by('f.id')
->order_by('f.sort', 'asc')
->get()->result();

return $this->db->select('*')
->from('v_category')
->where('upid',$upid)
->order_by('sort','asc')
->order_by('id','desc')
->get()->result();

return $this->db->get_where('category', array('id' => $id))->row();

return $this->db->get_where('v_category', array('upid' => $upid))->result();

$this->db->where('host',$host)->where('id !=',$id)->from('host')->count_all_results();