laravel migrate时报错:Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes

在按照文档执行php artisan migrate时报错。

SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes (SQL: alter table `users` add unique `users_email_unique`(`email`))

　　解决方法

namespace AppProviders;

use IlluminateSupportServiceProvider;
use IlluminateSupportFacadesSchema;

class AppServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        Schema::defaultStringLength(191);
    }
}