firefly-iii/database/migrations/2016_10_09_150037_expand_transactions_table.php

<?php

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

/**
 * Class ExpandTransactionsTable
 */
class ExpandTransactionsTable extends Migration
{
    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        //
    }

    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::table(
            'transactions', function (Blueprint $table) {
            $table->smallInteger('identifier', false, true)->default(0);
        }
        );
    }
}