我想加入表codeigniter的最后添加的行

Question

public function getProduct1($sp_id){

        $this->db->select('*');
        $this->db->from('product');
        $this->db->where('pd_supplier',$sp_id);
        $this->db->where('pd_status',1);
        $this->db->join('stock','product.pd_code=stock.stock_product_id');
        $this->db->group_by('stock.stock_product_id'); 
        $this->db->where('stock.stock_qty < product.pd_min');
        $this->db->select_max('stock.stock_id');
        $this->db->order_by('stock.stock_id', 'desc');
        $query = $this->db->get();
        $row = $query->result();
        return $row;
}

  

$ this-> db-> where（'stock.stock_qty

此代码仅检查产品表中产品数量表中库存表中最后输入的数量