文件：Composer.json --------------------------------------

 {
        "name": "laravel/laravel",
        "description": "The Laravel Framework.",
        "keywords": ["framework", "laravel"],
        "license": "MIT",
        "type": "project",
        "require": {
            "php": ">=7.0.0",
            "barryvdh/laravel-debugbar": "^3.0",
            "creativeorange/gravatar": "~1.0",
            "doctrine/dbal": "^2.5",
            "fideloper/proxy": "~3.3",
            "google/recaptcha": "^1.1",
            "intervention/image": "^2.4",
            "jaybizzle/laravel-crawler-detect": "1.*",
            "jeremykenedy/laravel-exception-notifier": "^1.1",
            "jeremykenedy/laravel-https": "^1.1",
            "jeremykenedy/laravel-logger": "^1.0.1",
            "jeremykenedy/laravel-roles": "^1.1",
            "jeremykenedy/laravel2step": "^1.0.2",
            "jeremykenedy/uuid": "^3.1",
            "laravel/framework": "5.5.*",
            "laravel/socialite": "^3.0",
            "laravel/tinker": "~1.0",
            "laravelcollective/html": "^5.5",
            "pusher/pusher-php-server": "^3.0",
            "rap2hpoutre/laravel-log-viewer": "^0.10.4",
            "socialiteproviders/37signals": "^3.0",
            "socialiteproviders/generators": "^2.0",
            "socialiteproviders/instagram": "^3.0",
            "socialiteproviders/twitch": "^3.0",
            "socialiteproviders/youtube": "^3.0"
        },
    }

//文件app.php ----------------------------------------

 'providers' => [
        SocialiteProviders\Manager\ServiceProvider::class,
        SocialiteProviders\Generators\GeneratorsServiceProvider::class,
  ],
  'aliases' => …

1452 - 无法添加或更新子行：外键约束失败 ( projectphp1707. #sql-e6c_cd, CONSTRAINT #sql-e6c_cd_ibfk_1FOREIGN KEY ( order_id) REFERENCES tbl_order( order_id))

表格1：

表2：

CREATE TABLE `tbl_order` (
  `order_id` int(11) NOT NULL,
  `user_id` int(11) DEFAULT NULL,
  `cus_fullname` varchar(50) COLLATE utf8_unicode_ci NOT NULL,
  `total_price` double DEFAULT NULL,
  `active` tinyint(1) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;

CREATE TABLE `tbl_payment` (
  `pay_id` int(50) NOT NULL,
  `pro_id` int(15) NOT NULL,
  `pay_name` varchar(255) CHARACTER SET utf8 COLLATE utf8_unicode_ci NOT NULL,
  `pay_email` varchar(255) CHARACTER SET utf8 COLLATE …

SQLSTATE [01000]：警告：1265第一行的列“ pay_totals”数据被截断

public function order(Request $req){
        $order = new Order;
        $order->pay_number = $req->checkout_number;
        $order->pay_totals = $req->checkout_total;
        $order->save();
        return redirect(route('pay'))->with('message','Sending infomation successfully');
    }

刀：

<input type="text" name="checkout_total" value="{{Cart::subTotal('0') }} ">

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