SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long； max key length

PS D:\Centos\PHPstudyWWW\dcatAdmin> php artisan admin:install
Migration table created successfully.
Migrating: 2014_10_12_000000_create_users_table

   Illuminate\Database\QueryException  : 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`))

  at D:\Centos\PHPstudyWWW\dcatAdmin\vendor\laravel\framework\src\Illuminate\Database\Connection.php:664
    660|         // If an exception occurs when attempting to run a query, we'll format the error
    661|         // message to include the bindings with SQL, which will make this exception a
    662|         // lot more helpful to the developer instead of just the database's errors.
    663|         catch (Exception $e) {
  > 664|             throw new QueryException(
    665|                 $query, $this->prepareBindings($bindings), $e
    666|             );
    667|         }
    668|

  Exception trace:

  1   Doctrine\DBAL\Driver\PDO\Exception::("SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes")
      D:\Centos\PHPstudyWWW\dcatAdmin\vendor\doctrine\dbal\lib\Doctrine\DBAL\Driver\PDO\Exception.php:18

  2   Doctrine\DBAL\Driver\PDO\Exception::new(Object(PDOException))
      D:\Centos\PHPstudyWWW\dcatAdmin\vendor\doctrine\dbal\lib\Doctrine\DBAL\Driver\PDOStatement.php:119

  Please use the argument -v to see more details.
PS D:\Centos\PHPstudyWWW\dcatAdmin>

laravel报错 “ SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 1000 bytes”

原因：mysql版本较低

解决办法：app\Providers\AppServiceProvider.php 下修改 boot() 方法添加如下代码

Schema::defaultStringLength(191);

完整代码

<?php

namespace App\Providers;

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

    /**
     * Register any application services.
     *
     * @return void
     */
    public function register()
    {
        //
    }
}