php - 在 PHP 中调用 null 的成员函数 query()

Question

运行 PHP 代码时出现以下错误。

Call to a member function query() on null

下面是代码，

function fetch_url($url_code) {
    $query = "SELECT * FROM `urls` WHERE `url_code` = ? ";

    $result = $this->db->query($query, array($url_code));
    if ($result) {
        return $result;
    } else {
        return false;
    }
}

请指导我如何消除此错误。

Answer 1

this->db->query function need only SQL Code. not like PDO.

确保库已加载

在config/autoload.php中添加$autoload['libraries'] = array('database');

<小时/>

试试这个

function fetch_url($url_code) {

    $query = $this->db->query("SELECT * FROM urls WHERE url_code = '$url_code' ");
    $result = $query->result_array(); # setting array to objective 
    $count = count($result); # get count

    if (!empty($count)) {
        return $result;
    } 
    else {
        return false;
    }
}