Removing Spam Posts

I have hit a roadblock here. I have posts table in my database and a spam table which basically stores if the users mark the posts as spam or inappropriate content. And I know how to write an algorithm to remove but there's a problem with how I think I can do this. If I include or check inappropriate content in Laravel when user logs in then It would run multiple times with each user and I don't want that which is how I thought I could code.
Another way is to check when displaying posts. If I do that on the controller it won't solve anything as it runs with each user and is not a viable option. So how can I implement this? And what does this type of things are called for lack of technical terms I can't say exactly what this type of problem is called.