PHP：使用数据库中的 foreign 将用户表提取到 Auth 表 [已关闭]

问：

我尝试获取用户数据并从数据库中获取到 Auth 数据库表数据。这整件事发生在RDBMS。在这种情况下，我遇到了一些错误。

当我编写此代码时，我遇到了一些错误，但我无法解决该错误

法典

<?php
require_once "Database.class.php";

class User
{ 
  private $conn;
  public function __call($name,$arguments){
    if(substr($name, 0, 3)== "get"){
      return $this->__get($property);
    }esleif(substr($name, 0, 3)== "set"){
      return $this->__set($name,$arguments[0]);
    }
  }

  public function __call($name, $arguments)
  {
    //$name="getFirstName";    //ForChecking Purpose
    $property = preg_replace("/[^0-9a-zA-Z]/","",substr($name,3));
    $property = strtolower(preg_replace('/\B([A-Z])/','_$1',$property));
    //echo $property; //ForChecking Purpose

  if(substr($name,0,3)== "get"){
    return $this->__get($property);
  }elseif(substr($name, 0, 3) == "set"){
    return $this->__set($name,$arguments[0]);
  }
  }


  public static function signup($user, $pass, $email, $phone)
  {
    $option = [
      'cost' => 8,
    ];
    $pass = password_hash($pass, PASSWORD_BCRYPT, $option);
    $conn = Database::getConnection();
    $sql = "INSERT INTO `Auth` (`username`, `password`, `email`, `phone`, `blocked`, `active`)
    VALUES ('$user', '$pass', '$email', '$phone', '0', '1');";
    $error = false;
    if ($conn->query($sql) === true) {
      $error = false;
    } else {
      // echo "Error:" . $sql . "<br>" . $conn->error;
      $error =  $conn->error;
    }
    //$conn->close();
    return $error;
  }

  public static function login($user, $pass)
  {
    $query = "SELECT * FROM `Auth` WHERE `username` = '$user'";
    $conn = Database::getConnection();
    $result = $conn->query($query);
    if ($result->num_rows == 1) {
      $row = $result->fetch_assoc();
      if (password_verify($pass, $row['password'])) {
        return new User($row['username']);
      } else {
        return false;
      }
    } else {
      return false;
    }
  }

  public function __construct($username)
  {
    $this->conn = Database::getConnection();
    $this->username = $username;
    $sql = "SELECT `id` FROM `Auth` WHERE `username`='$username' LIMIT 1";
    $result = $this->conn->query($sql);
    if($result->num_rows){
      $row = $result->fetch_assoc();
      $this->id = $row['id']; //updating from the database
    }else{
    throw new Exception("Username doesn't exist");
  }

  //this function helps to set the data from the database
  private static function __set($var, $data)
  {
    if (!$this->conn) {
      $this->conn = Database::getConnection();
    }
    $sql = "UPDATE `users` SET `$var`='$data' WHERE `id` = '$this->id';";
    if ($this->conn->query($sql)) {
      return true;
    } else {
      return false;
    }
  }

  
  //this function helps to retrieve data from the database
  private function __get($var)
  {
    if (!$this->conn) {
      $this->conn = Database::getConnection();
    }
    $sql = "SELECT `$var` FROM `users` WHERE `id` = '$this->id'";
    $result = $this->conn->query($sql);
    if ($result->num_rows()) {
      return $result->fetch_assoc()["$var"];
    } else {
      return null;
    } 
  }

  public function authenticate()
  {
  }
}

错误信息

但是不明白错误是什么，错误是提到大括号的。