for example a website where users can vote on questions (up and down) with this model:

```
    users(id)

    questions(id)

    votes(id,userId,questionid,vote)  
-- vote can be +1 or -1, or probably better bit 0 and 1

```

I'm thinking that when there are going to be lots of `questions` with lots of votes, there are going to be performance issues, especially when showing the list of questions, so

would it make sense to add a column to the questions like this:

```
questions(id, votessum)

```

and each time somebody votes besides doing an `insert into the votes questions also to update the questions` and set it's `votessum column`