Using question mark character in Rails/ActiveRecord column name

Question

In keeping with Ruby's idiom of using a question mark in boolean methods (e.g. person.is_smart?), I'd like to do the same for an ActiveRecord field in Rails:

rails generate model Person is_smart?:boolean 

I haven't actually run the above statement. I assume that database fields can't have a question mark in them. Will rails deal with this appropriately? Is the best practice to simply leave question marks off of models?

Using Rails 3.2.8

Answer 1

Rails will automatically generate the method smart? if there is a field named 'smart'.

Answer 2

One "gotcha" to be aware of if you happen to use :enum in your model, since this stores the value as an integer. The question mark attr method provided by active record expects to evaluate 0 or 1 as false / true respectively in the database. For example:

class Person   enum mood: ['happy', 'sad', 'bored'] end  p = Person.new(mood: 'happy') # this would store mood as 0 in db p.mood? #=> false  p.mood = 'sad' # saves as 1 in db p.mood? #=> true  p.mood = 'bored' # saves as 2 in db p.mood? #=> true 

to see how this method works, see rails source