CodeIgniter：如何将 get() 活动记录与以前的活动记录一起使用两次？答案

【问题标题】：CodeIgniter: How to use the get() active record twice with previous active records?CodeIgniter：如何将 get() 活动记录与以前的活动记录一起使用两次？
【发布时间】：2013-04-05 09:14:44
【问题描述】：

我在模型下有如下功能如图..

    public function get_products($category, $brand, $filter, $page, $limit) {
    // output
    $output = "";
    // offset
    $offset = $limit * ($page - 1);
    // query for pagination
    $this->db->select("*");
    $this->db->from("products");
    $this->db->where("category", $category);
    if ($brand != "all") {
        $this->db->where("brand", $brand);
    }
    // first time use
    $query = $this->db->get();
    $total_rows = $query->num_rows();
    $this->db->limit($limit, $offset);
    switch ($filter) {
        case 'latest':
        $this->db->order_by("released", "ASC");
        break;
        case 'most-viewed':
        $this->db->order_by("views", "ASC");
        break;
        case 'price-low-to-high':
        $this->db->order_by("price", "DESC");
        break;
        case 'price-high-to-low':
        $this->db->order_by("price", "ASC");
        break;
    }
    //second time use
    $query = $this->db->get();

在这里，我想使用select、from 和where 和2 个this->db->get()，如您所见，但查询在运行第一个get() 后结束。那么有没有办法做到这一点？或者我必须写两次活动记录？

我尝试这样做的原因是在限制分页 total_rows 配置之前获取 num_rows。

【问题讨论】：

标签： codeigniter activerecord get

【解决方案1】：

你可以这样做。

public function get_products($category, $brand, $filter, $page, $limit) 
{
    $output = "";
    $offset = $limit * ($page - 1);

    $this->getQuery($category , $brand);
    $query = $this->db->get();

    $total_rows = $query->num_rows();
    //Call the query again 
    $this->getQuery($category , $brand);
    /*  This time limit and order will be applied to the query */   
    $this->db->limit($limit, $offset);

    switch ($filter) {
        case 'latest':
        $this->db->order_by("released", "ASC");
        break;
        case 'most-viewed':
        $this->db->order_by("views", "ASC");
        break;
        case 'price-low-to-high':
        $this->db->order_by("price", "DESC");
        break;
        case 'price-high-to-low':
        $this->db->order_by("price", "ASC");
        break;
    }
    //Run query now
    $query2 = $this->db->get();
}
/* This will only generate the query and will not run it */
function getQuery($category , $brand){

    $this->db->select("*");
    $this->db->from("products");
    $this->db->where("category", $category);
    if ($brand != "all") {
        $this->db->where("brand", $brand);
    }
}

【讨论】：