问题:运行迁移文件报错
   Illuminate\Database\QueryException
  SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes (SQL: alter table `users` add unique `users_email_unique`(`email`))
  at E:\phpstudy_pro\WWW\shopapi\vendor\laravel\framework\src\Illuminate\Database\Connection.php:712
    708▕         // If an exception occurs when attempting to run a query, we'll format the error
    709▕         // message to include the bindings with SQL, which will make this exception a
    710▕         // lot more helpful to the developer instead of just the database's errors.
    711▕         catch (Exception $e) {
  ➜ 712▕             throw new QueryException(
    713▕                 $query, $this->prepareBindings($bindings), $e
    714▕             );
    715▕         }
    716▕     }
  1   E:\phpstudy_pro\WWW\shopapi\vendor\laravel\framework\src\Illuminate\Database\Connection.php:501
      PDOException::("SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes")
  2   E:\phpstudy_pro\WWW\shopapi\vendor\laravel\framework\src\Illuminate\Database\Connection.php:501
      PDOStatement::execute()这是由于Laravel 默认使用 utf8mb4 字符, 包括支持在数据库存储「 表情」 。 如果你正在运行的 MySQL release 版本低于5.7.7 或 MariaDB release
 版本低于10.2.2 , 为了MySQL为它们创建索引, 你可能需要手动配置迁移生成的默认字符串长度, 你可以通过调用 AppServiceProvider 中的
 Schema::defaultStringLength 方法来配置它:
解决办法
1.  E:\phpstudy_pro\WWW\shopapi\app\Providers\AppServiceProvider.php
<?php
namespace App\Providers;
use Illuminate\Support\ServiceProvider;
use Illuminate\Support\Facades\Schema;
class AppServiceProvider extends ServiceProvider
{
    /**
     * Register any application services.
     *
     * @return void
     */
    public function register()
    {
        //
    }
    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        //
        Schema::defaultStringLength(191);
    }
}
这两句代码 加上
use Illuminate\Support\Facades\Schema;
public function boot()
    {
        //
        Schema::defaultStringLength(191);
    }
再次执行迁移文件:
 php artisan migrate










