Ruby on Rails - Increment and decrement
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If you're using rails and have an integer column in database that you want to increment or decrement, rails provides a nice abstraction for you to use. Normally you'd have do something like this:
def increase_credits
update_attributes(:credits => credits + 1)
end
Then you can call it like:
@user.increase_credits
With the increment and decrement you can do it this way:
@user.increment!(:credits)
or
@user.decrement(:credits, 2) # decrease credits by 2
It just saves setting up the method and allows you to pass an integer to increment by!
Decrement: http://apidock.com/rails/ActiveRecord/Base/decrement! Increment: http://apidock.com/rails/ActiveRecord/Base/increment%21