Laravel，relationship

    //檔案：database/migrations/日期_編號_create_posts_table.php
    public function up()
    {
        Schema::create('posts', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('user_id')->unsigned(); //正數
            $table->string('title');
            $table->text('content');
            $table->timestamps();
        });
    }

//下指令
php artisan migrate:refresh

資料庫的posts資料表將會增加user_id這個欄位