laravel-migration

php artisan make:migration wechat_admin –create=admin

php artisan make:migration create_userNAME 后面跟行为和表名

错误信息

[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))
[PDOException]
SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes

原因
laravel匹配的是新版本的mysql.而旧版本的mysql长度不够。

<?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()
    {
        //
    }
}

Error Base table or view already exists: 1050 Table ‘users’ already exists

<?php
use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;
class CreateUsersTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::dropIfExists('users');
        Schema::create('users', function (Blueprint $table) {
            $table->increments('id');
            $table->string('name');
            $table->string('email')->unique();
            $table->string('password');
            $table->rememberToken();
            $table->timestamps();
        });
    }
    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('users');
    }
}

第一种，如果刚刚建立起table，并没有数据，可以选择rollback或者reset，即使用

$ php artisan migrate:rollback
1
或者

$ php artisan migrate:refresh
1
值得注意的是，rollback这个命令默认选项只会向之前恢复一次migration，而refresh将会把所有migration全部重置，相当于

$ php artisan migrate:reset
$ php artisan migrate

如果迁移已经执行，先回滚
php artisan migrate:rollback

然后删除迁移文件，运行
composer dump-autoload

php artisan migrate:reset