Php 使用数组和mysqli仅选择一个表行

下表和函数属于PHP MySQL数据库集成（）。该函数显示名为“files”的表的所有字段。我想用usr字段扩展表，因为在这之后，我只想显示与之前通过变量传递的用户匹配的行。我的步骤（用于测试）我已使用usr字段扩展了表，并以usr的形式进入（'admin'），并尝试使用以下代码：

$this->options['db_table'].'` WHERE `usr`=admin';  

但不要什么都不展示……有什么想法吗

扩展表（最终表）：

PHP函数：

<?php
$options = array(
    'delete_type' => 'POST',
    'db_host' => 'localhost',
    'db_user' => 'root',
    'db_pass' => '',
    'db_name' => 'example',
    'db_table' => 'files'
);

….

protected function set_additional_file_properties($file) {
        parent::set_additional_file_properties($file);
        if ($_SERVER['REQUEST_METHOD'] === 'GET') {
            $sql = 'SELECT `id`, `type`, `title`, `description` FROM `' 
            .$this->options['db_table'].'` WHERE `name`=?'; 
            $query = $this->db->prepare($sql);
            $query->bind_param('s', $file->name);
            $query->execute();
            $query->bind_result(
                $id,
                $type,
                $title,
                $description
            );
            while ($query->fetch()) {
                $file->id = $id;
                $file->type = $type;
                $file->title = $title;
                $file->description = $description;
            }
        }

<?php
$options = array(
    'delete_type' => 'POST',
    'db_host' => 'localhost',
    'db_user' => 'root',
    'db_pass' => '',
    'db_name' => 'example',
    'db_table' => 'files'
);

….

protected function set_additional_file_properties($file) {
        parent::set_additional_file_properties($file);
        if ($_SERVER['REQUEST_METHOD'] === 'GET') {
            $sql = 'SELECT `id`, `type`, `title`, `description` FROM `' 
            .$this->options['db_table'].'` WHERE `name`=?'; 
            $query = $this->db->prepare($sql);
            $query->bind_param('s', $file->name);
            $query->execute();
            $query->bind_result(
                $id,
                $type,
                $title,
                $description
            );
            while ($query->fetch()) {
                $file->id = $id;
                $file->type = $type;
                $file->title = $title;
                $file->description = $description;
            }
        }