polr/database/migrations/2017_12_21_095425_create_api_quota_index.php

<?php

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

class CreateApiQuotaIndex extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::table('links', function (Blueprint $table)
        {
            $table->index(
                ['created_at', 'creator', 'is_api'],
                'api_quota_index'
            );
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::table('links', function (Blueprint $table)
        {
            $table->dropIndex('api_quota_index');
        });
    }
}