我是codeigniter的初学者.
我有这样的查询,我想在codeigniter中使用此查询

SELECT sum(price) 
FROM (SELECT price
      FROM items
      ORDER BY price DESC
      LIMIT 3
) AS subquery;

我做了

$this->db->select('SUM(price)');
$this->db->select('price');
$this->db->from('items');
$this->db->order_by('price desc');
$this->db->limit(3);
$this->db->get();

这给出了这样的输出

SELECT sum(price), price
      FROM items
      ORDER BY price DESC
      LIMIT 3;

我能做什么？

解决方法:

这样使用

$this->db->select_sum('price');
$this->db->select('price');
$this->db->from('items');
$this->db->order_by('price desc');
$this->db->limit(3);
$this->db->get();