Hey everybody, I've got a table that contains addresses. Addresses belong_to users. When a new address is added, I would like to avoid duplicates. The model should check to see if it is exactly the same as an existing address, and if it is, instead of saving the address and returning a new record, I would like it to load the old record. I'm thinking something like this: def save if old_record = this_is_a_duplicate_record this.id = old_record.id this.reload else super end end ... is this the way to do it? Or is there a better/safer method? Thanks, Tyler
on 2007-06-05 22:14
on 2007-06-06 00:06
Personally, I think that's a bad idea. Overriding the behavior of save seems rather dangerous and confusing. The save method should either return true or false (indicating validation or database errors encountered during save). It should not attempt to return an instance of some other object. Instead you should allow the normal validation system to provide feedback to the user that they are attempting to insert a duplicate address. I'm thinking something like: Address < ActiveRecord::Base belongs_to :user validate_uniqueness_of :address, :scope => [ :user_id, :city, :state, :zip ] validate_uniqueness_of :city, :scope => [ :user_id, :address, :state, :zip ] validate_uniqueness_of :state, :scope => [ :user_id, :address, :city, :zip ] validate_uniqueness_of :zip, :scope => [ :user_id, :address, :city, :state ] end Now in your controller/view you could then provide them a link or possibly redirect to some view of the user showing the existing address. But, this type of thing should not happen anywhere in the model layer.