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    I need only the customer's first and last name and the total number of their orders over $100. This would result in two queries and redundant data being returned, which is unacceptable. Commented Feb 25 at 19:05
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    @MrChudz not if customer name is a domain object Commented Feb 25 at 20:26
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    @MrChudz - if I understood you correctly, your comment suggests that your domain objects closely mirror the database tables, while your DTOs are more in line with the use cases of your application (which ideally should be what the domain objects are doing). This design is what makes translating the queries unwieldy and far from optimal. I think this is also what Basilevs was getting at. Commented Feb 25 at 21:01
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    @MrChudz "Often, we need to return only a subset of a domain model’s properties" - I know people call these entities "models", but that's a slight misuse of the term, and is now causing some confusion, because it's not what we're talking about when we say "domain model". It's not a particular class: it's the set of all the classes + the associated high level logic that forms the core of your domain layer and captures the essential aspects of the problem the application is tackling (meaning it is an effective in-code representation of it, supporting the needs of the application). 1/2 Commented Feb 26 at 20:31
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    So, it's not that there's some class that is designated a "domain model" and then you sometimes need to return "a subset of a domain model’s properties"; instead, if it's a legit use case, such a subset and the logic surrounding it is in some way represented within the the domain model (in this broader sense), it is a part of it (maybe it's a separate class, or a narrower interface, or maybe a part that you also reuse to compose the full object - how exactly is up to you and your understanding of the problem domain). Otherwise your domain model is not representative of your problem domain. 2/2 Commented Feb 26 at 20:31