对PHP写库存管理系统中的库存查询记录功能进行代码生成

<?php
require_once "db_connection.php";

class InventoryQueryRecord {
    private $conn;

    public function __construct() {
        // 初始化数据库连接
        $this->conn = db_connection();
    }

    public function addRecord($user_id, $product_id, $quantity) {
        // 添加库存查询记录
        $query = "INSERT INTO inventory_query_records (user_id, query_time, product_id, quantity)
                  VALUES ('$user_id', NOW(), '$product_id', '$quantity')";
        $result = $this->conn->query($query);

        if ($result) {
            return true;
        } else {
            return false;
        }
    }

    public function deleteRecord($id) {
        // 删除库存查询记录
        $query = "DELETE FROM inventory_query_records WHERE id = '$id'";
        $result = $this->conn->query($query);

        if ($result) {
            return true;
        } else {
            return false;
        }
    }

    public function getRecords($user_id) {
        // 获取指定用户的库存查询记录
        $query = "SELECT * FROM inventory_query_records WHERE user_id = '$user_id'";
        $result = $this->conn->query($query);

        if ($result->num_rows > 0) {
            $records = array();
            while ($row = $result->fetch_assoc()) {
                $records[] = $row;
            }
            return $records;
        } else {
            return false;
        }
    }
}
?>

<?php
require_once "InventoryQueryRecord.php";

$product_id = $_POST['product_id'];
$quantity = $_POST['quantity'];

// 进行库存查询操作

$queryRecord = new InventoryQueryRecord();
$queryRecord->addRecord($user_id, $product_id, $quantity);

// 返回查询结果
?>