Question

I need an extra field for custom sorting for my Profile model. So i need to initialize it on column addition.

Now I see two approaches to do that:

1. Update field after migrations via rake task or at production console.

2. Write down something like that

   Profile.all.each { |p| p.update_attribute :sorted_at, p.created_at }
   

   in separate migration file.

Is second solution good or bad? And may be is there 3rd solution which is much better than these?

Answer 1

My opinion is to update the fields in the migration.

Pros:

• That’s what migrations are for (?)
• No more hassles with tasks. Because one can easily forget to run the task, and in the case of errors or exceptions you have only one place to look at instead of 2.

Cons:

• none that i can think of

Also, it’s a good idea to use update_all instead of looping through each record and updating because of the obvious performance increase.