Ruby on Rails. Increase integer in database

Question

I have created a website using Ruby on rails and have a database with points for my users. Every user has points so I would refer to it as @user.points. I am able to view the points by using:

<%= user.points %>

I am trying to increase these points from my page as users complete a certain action. So I tried doing:

<% @user.points += 100 %>

but this doesn't seem to work. I feel there is a simple solution or I am overseeing something.

Answer 1

You can use increment(attribute, by = 1):

Initializes attribute to zero if nil and adds the value passed as by (default is 1). The increment is performed directly on the underlying attribute, no setter is invoked. Only makes sense for number-based attributes. Returns self.

@user.increment(:points,  100)

Example:

 => user = User.last
 => user.points
 =# 100
 => user.increment(:points, 100)
 => user.points
 =# 200
 => user.increment(:points, 100)
 => user.points
 =# 300
 =# ......