Myujth

I have a form with a checkbox that users tick to provide consent. When this form is posted the Users table is updated with a field that confirms consent is provided. However I also want record the date/time that consent was provided. To this end I was hoping to have a 'user_consent' field that would store 'yes' and a user_consent_agreed' field that would store the date/time that the user_consent field was updated.

I know I can add timestamps to a table on creation but this will change when any attribute is updated, I need to record time/date in its own field when the consent attribute changes.

I would just have one column in the table consented_at, which is of type DateTime. When they consent, you update that column:

user.update_column :consented_at, DateTime.now

I used consented_at to keep it inline with created_at and updated_at

This way, you can tell if a person has consented or not and when they consented (if they did).

if user.consented_at?
 # consented and you have the time in consented_at
else
 # never consented
end

No real need to have a boolean column and a time since checking the time column will return true or false anyway.

As already suggested, add a consented_at column to hold the timestamp.

To automatically update this column when the value of consented changes, add a before_save callback to your model:

class User < ApplicationRecord

 before_save do
 self.consented_at = Time.zone.now if consented_changed?
 end

end

Note that this will set consented_at on any change to consented, even setting it to false. If that's not what you want, you can adjust the code inside the callback as desired.

See https://api.rubyonrails.org/classes/ActiveRecord/Callbacks.html for more on model callbacks. See https://api.rubyonrails.org/classes/ActiveModel/Dirty.html for more on how to detect changes.