Attaching guest checkout orders to user accounts

Question

I'm stuck with a specific requirement on my magento shop. I have enabled the guest checkout method on magento to remove the necessity of registering.

But now this information is useless for providing customized experience to the customer in future if he registers himself. When the person who has used guest checkout previously, registers himself on my shop, I want his previous orders to get attached with his account, so that his whole shopping history can be combined to give him better shopping experience. Is there any possibility to do that within the possibilities of magento. If any of you have done that previously, please give any pointers to achieve this. Please, feel free to provide other better alternatives, if my thoughts are wrong somewhere. I'll greatly appreciate any help, thanks in advance.

Edit: I got success in editing customer's name and other options, but still looking for some help to attach the customer's account to the order, so that it is available in the order history of customer.

Answer 1

While this not technically an answer, the information below is somewhat related and could be of use.

Some of my customers tried out similar approaches and as a hindsight I can assure you that doing something like that might not be a good idea, at least without asking customer confirmation. There is a number of issues:

1. By default Magento doesn't ask user to confirm their e-mail ownership and this allows people to "fish" orders by guessing purchaser e-mail addresses. Knowing what they bought can open doors to all kind of social engineerings. It also allows me to "capture" order and send it to another location, effectively stealing stuff somebody ordered.
2. People sometimes buy stuff anonymously intentionally, even though they have account. Attaching those orders to their accounts can be serious breach of privacy.
3. Once you invoice your order you have to understand that invoice is a binding legal document. Invoice is also directly associated with order and once you attach it to account there could be a conflict between user profile data and guest order data. Which one of those is going to have precedence? You don't want to mess with people profiles and you really don't want to mess with invoices either.

It could be that you have already all this figured out, but for rest of the folks this is just a warning that fooling around with order owners may have unwanted consequences.