sorry if it’s duplicate, I’ve been looking for something similar before posting, but no success.
So basically I need an up/down rating system ( it’s very similar to the one here on stackoverflow ).
I have 6 rateable models, so polymorphic association seem to be the best option.
But since this table will probably hold a solid number of records, won’t it take too much time to get the item rating ( upvotes_count - downvotes_count )?
I actually though about adding a new row to each and every rateable model, something like current_rating_value. So that this value will be changed every time the rating object will be created/destroyed.
Could you please advice, what might be a better option in this case? Extra UPDATE call to change the current_rating_value or an extra SELECT(SUM…) call to calculate it?
Depending on how much traffic you get loading these models it could tax resources more then desired. I’ve ended up using acts_as_votable gem in my projects. Its very easy to make a model votable and it also caches the data which is also awesome.