如何将此查询转换为codeigniter的linq

Question

我不明白如何将此查询转换为codeigniter linq

SELECT prdctSubCatId 
FROM productinfo 
WHERE prdctSubCatId = (
  SELECT prdctSubCatId 
  FROM productinfo 
  WHERE id='27'

） 而不是id = '27'我想传递id = $ id，那我该怎么做呢

Answer 1

$this->db->select('prdctSubCatId')->from('productinfo');
$this->db->where('`prdctSubCatId`= (SELECT `prdctSubCatId` FROM `productinfo` WHERE id=27 )', NULL, FALSE);

Answer 2

    $this->db->select('prdctSubCatId');
    $this->db->where('id',27);
    return $this->db->get('productinfo')->result_array();

Answer 3

只需使用

$query = $this->db->query("SELECT prdctSubCatId FROM productinfo WHERE prdctSubCatId=27");
$result = $query->result_array();
return $result;