Question

I am trying to create a point system in my program similar to stack overflow i.e. when the user does some good deed (activity) his/her points are increased. I am wondering what is the best way to go about implementing this in terms of db schema + logic.

I can think of three options:

1. Add an extra field called points in the users table, and everytime a user does something, add it to that field (but this will not be able to show an activity of sorts)
2. Create a function which will run everytime the user does good deed and it calculates from scratch the value and updates the points field
3. Calculate everytime using a function without any points field.

What is the best way to go about this? Thank you for your time.

Answer 1

Personally, I would use the second option to approach this problem.

The first option limits functionality, so I eliminate that right away.

The third option is inefficient in terms of performance – it is likely that you will be fetching that number a lot, and, if your program is anything like stackoverflow, perhaps showing (calculating) that number many times per pageview/action.

To me, the second option is a decent hybrid solution. Normally, I hate having duplicated data in my system (actions and points, rather than one or the other), but in this case, an integer field is a rather small amount of space per user that saves you a lot of time in recalculating the values unnecessarily.

We must, at times, trade data storage space for performance or vice versa, and I would say that #2 is a trade-off that greatly benefits the application.