nexusphp/database/migrations/2021_06_08_113437_create_allowedemails_table.php

<?php

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

class CreateAllowedemailsTable extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        if (Schema::hasTable('allowedemails')) {
            return;
        }
        Schema::create('allowedemails', function (Blueprint $table) {
            $table->integer('id', true);
            $table->mediumText('value');
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('allowedemails');
    }
}