View file database/migrations/2018_04_20_180006_create_bookmarks_table.php

<?php

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

return new class extends Migration {
    public function up(): void
    {
        if (! Schema::hasTable('bookmarks')) {
            Schema::create('bookmarks', function (Blueprint $table) {
                $table->increments('id');
                $table->integer('user_id');
                $table->integer('topic_id');
                $table->integer('count_posts');

                $table->index('topic_id');
                $table->index('user_id');
            });
        }
    }

    public function down(): void
    {
        Schema::dropIfExists('bookmarks');
    }
};