众所周知，laravel的ORM使用起来非常顺手，并且强大，那么如果我们不用laravel也想用ORM该怎么做了

1、composer 安装需要的组件

composer require illuminate/database

2、初始化组件，简单理解就是配置数据库的链接信息给ORM，将这个信息在入口文件处引入

<?php
$database = [
    'driver' => 'mysql',
    'host' => env('DB_HOST'),
    'database' => env('DB_NAME'),
    'username' => env('DB_USER'),
    'password' => env('DB_PASSWORD'),
    'charset' => 'utf8',
    'collation' => 'utf8_unicode_ci',
];

use Illuminate\Database\Capsule\Manager as Capsule;

$capsule = new Capsule;

//创建一个数据库的链接
$capsule->addConnection($database);

//静态可访问
$capsule->setAsGlobal();

//启动Eloquent，实际上就是解析链接信息，开始建立数据库的链接
$capsule->bootEloquent();

3、使用ORM

<?php

namespace app\models;

use Illuminate\Database\Eloquent\Model;

class Orders extends Model
{
    protected $table = 'orders';
}

3.1、使用DB

use Illuminate\Database\Capsule\Manager as DB;
public function index()
{
    DB::table('users')->where('id', 1)->first();
}