我想使用laravel迁移数据库。
我尝试使用以下命令：php artisan migrate:fresh --seed并出现以下错误：

Migrating: 2019_10_28_130723_alter_users_table

   Illuminate\Database\QueryException  : SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MariaDB ser
ver version for the right syntax to use near 'CHARactER SET utf8mb4 DEFAULT 0 NOT NULL COLLATE `utf8mb4_unicode_ci`' at line 1 (SQL: ALTER TABLE users CHANGE deductible_amount deductible_a
mount BIGINT UNSIGNED CHARactER SET utf8mb4 DEFAULT 0 NOT NULL COLLATE `utf8mb4_unicode_ci`)

  at C:\xampp\htdocs\project\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\PDOException::("SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MariaDB s
erver version for the right syntax to use near 'CHARactER SET utf8mb4 DEFAULT 0 NOT NULL COLLATE `utf8mb4_unicode_ci`' at line 1")
      C:\xampp\htdocs\project\vendor\doctrine\dbal\lib\Doctrine\DBAL\Driver\PDOConnection.php:63

  2   PDOException::("SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the
 right syntax to use near 'CHARactER SET utf8mb4 DEFAULT 0 NOT NULL COLLATE `utf8mb4_unicode_ci`' at line 1")
      C:\xampp\htdocs\project\vendor\doctrine\dbal\lib\Doctrine\DBAL\Driver\PDOConnection.php:61

  Please use the argument -v to see more details.

这是我的2019_10_28_130723_alter_users_table迁移文件的内容：

<?php

use Illuminate\Support\Facades\Schema;
use Illuminate\Database\Schema\Blueprint;
use Illuminate\Database\Migrations\Migration;

class AlterUsersTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::table('users',function (Blueprint $table) {
            $table->renameColumn('active','is_active');
            $table->dropColumn([
                                    'settings','google_id','github_id','telegram_notif','income','email_notif','sms_notif','temppass','storm_id',]);
            $table->unsignedBigInteger('deductible_amount')->change();
            $table->softDeletes();
        });
    }



    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::table('users',function (Blueprint $table) {
            $table->renameColumn('is_active','active');
            $table->text('settings');
            $table->string('google_id')->nullable();
            $table->string('github_id')->nullable();
            $table->boolean('telegram_notif')->default(true);
            $table->string('income')->nullable();
            $table->boolean('email_notif')->default(true);
            $table->boolean('sms_notif')->default(false);
            $table->string('temppass')->nullable();
            $table->string('storm_id')->default(null)->nullable();
            $table->string('deductible_amount')->after('wallet')->default('0')->change();
            $table->dropSoftDeletes();
        });
    }
}

我不知道如何解决此问题。我已经搜索过了，但是大多数答案都提到必须转换为json的{​​{1}}字段，我的string表上没有json字段。 问题出在哪里，我该如何解决？