Domain queries in CQRS

Posted by JontyMC on Stack Overflow See other posts from Stack Overflow or by JontyMC
Published on 2010-01-06T19:06:34Z Indexed on 2010/04/08 10:53 UTC
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We are trying out CQRS. We have a validation situation where a CustomerService (domain service) needs to know whether or not a Customer exists. Customers are unique by their email address. Our Customer repository (a generic repository) only has Get(id) and Add(customer). How should the CustomerService find out if the Customer exists?

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