It is just an example for what I want like a fresh forum because id of posts and forums on my forum are pretty big, like 85323 or 93232...etc If members continue posting then it will generate big numbers like that.
That's why I asked this question, I am using vB 4.25 and PHP 7 thus I could not use Impex to import members on a fresh forum.
If you're worried about this affecting performance, don't worry, it will do no such thing. To truncate them just because you see the numbers getting larger is just paranoia. As stated, those numbers will keep growing with each post, so there's no real point in worrying about it.
Oh and I forgot to mention that by truncating them, you also run the risk of breaking internal links that your members may have linked to in threads.