Domain-driven design (DDD) is an approach to develop software for complex needs by connecting the implementation to an evolving model.

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Is it bad practice for services to share a database in SOA?

I have recently been reading Hohpe and Woolf's Enterprise Integration Patterns, some of Thomas Erl's books on SOA and watching various videos and podcasts by Udi Dahan et al. on CQRS and Event Driven ...
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Where we should put validation for domain model

I still looking best practice for domain model validation. Is that good to put the validation in constructor of domain model ? my domain model validation example as follows: public class Order { ...
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Can a system be 100% Data Driven?

My new boss has been working on this project for many years. I've only been here a few weeks, but I am not sure it's possible. He would like to design a system that is "100% data driven". So if we ...
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DDD + POCO does this makes sense?

DDD promotes rich domain models with behavior in it, POCO naked objects without any objects in it. Is it possible to have them both combined? I have a Multi Layer Solution Core - has POCO ...
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Validation and authorization in layered architecture

I know you are thinking (or maybe yelling), "not another question asking where validation belongs in a layered architecture?!?" Well, yes, but hopefully this will be a little bit of a different take ...
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DDD - Aggregate Roots - Dealing with Efficiency and Concurrency

First off, I'll admit that I'm a newbie to DDD and need to read the "blue book". I'm building a system that has an AggregateRoot of type "Match". Each Match can have a collection of "Votes" and also ...
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Recovering an anemic domain model into a multitier architecture

I have spent the past several days learning about domain driven design and attempting to apply it to a current project. I decomposed the problem domain into the canonical logical components: domain, ...
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2answers
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What is a value object in domain-driven design?

I have an entity and I've realised that there is a group of properties that work together. So, I moved them to a value object (together with their behavior) and now I have a reference from my entity ...
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With all of these services, how can I not be anemic?

Where do we draw the line between delegation and encapsulation of business logic? It seems to me that the more we delegate, the more anemic we become. However, delegation also promotes reuse and the ...
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Rich Domain Models — how, exactly, does behavior fit in?

In the debate of Rich vs. Anemic domain models, the internet is full of philosophical advice but short on authoritative examples. The objective of this question is to find definitive guidelines and ...
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Best practice or design patterns for retrieval of data for reporting and dashboards in a domain-rich application

First, I want to say this seems to be a neglected question/area, so if this question needs improvement, help me make this a great question that can benefit others! I'm looking for advice and help from ...
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What, in reference to DDD, is a bounded context?

When working through the book "Implementing Domain Driven Design" by Vaughn Vernon, I have been unable to gain a good grasp on what a bounded context actually is. The book defines a bounded context ...
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Where to validate domain model rules that depend on database content?

I'm working on a system that allows Administrators to define Forms that contain Fields. The defined Forms are then used to enter data to the system. Sometimes the Forms are filled by a human via a ...
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Unique Value Object vs Entity

Trying to convert some entities into value objects I am stuck in a case where what seems a value object must be unique within an aggregate. Suppose we have a Movie entity which makes the root of an ...
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6answers
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Application layer vs domain layer?

I am reading Domain-Driven Design by Evans and I am at the part discussing the layered architecture. I just realized that application and domain layers are different and should be separate. In the ...
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2answers
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Domain-Driven-Design - external dependencies in the Entity problem

I'd like to start Domain-Driven-Design, but there are several problems I'd like to solve before starting :) Let's imagine I have a Groups and Users and when user wants to join a group, I'm calling ...
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1answer
264 views

Cascading deletes from an aggregate root through out the entire aggregate doesn't make sense

Based on the same example for this question. Within the Pro ASP.Net MVC 4 by Adam Freeman, there is a discussion on aggregates and aggregate roots with a simple auction system. There are members who ...
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Inheritance using non-abstract base class

This post is based on the question http://stackoverflow.com/questions/49002/prefer-composition-over-inheritance/11758048#comment15634305_11758048. Some people said - check whether there is “is-a” ...
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1answer
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Should I be using separate 'domain' layer?

I have been reading a lot about domain layer and DDD. However I am still confused about it. To me they seem to be a fancy name for business classes however more modelled towards your application ...
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2answers
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How to work with large aggregate roots?

I'm learning DDD and yet I have more questions than answers. Let's consider a model of a directory containing enormous number of files. Here is how I see it: Directory is an Aggregate root. This ...
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1answer
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Doubts about architectural pattern for customizable standard enterprise application [duplicate]

My company needs to build an application to be rolled out for a lot of clients. This software will have many modules and functionalities, but some of these will need specific adjustments for some ...
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1answer
123 views

Domain-specific Interfaces

Are there any real benefits of using interfaces over abstract classes in a domain model? Does anyone have any experience using interfaces in a domain model in a real project? From a technical ...
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4answers
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Can an aggregate root hold references of members of another aggregate root?

I know that outside of aggregates I can't change anything inside an aggregate without passing by his root. That said I would like to know if an aggregate root can hold references of members (objects ...
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How do you handle shared concepts in a microservice architecture?

I am researching architectural patterns for an application I'm developing and a microservice approach seems like it would be a good choice but I am not sure how to handle interactions between the ...
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4answers
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Data access for composable applications

I'm wondering if anyone can share their thoughts, experience and guidance on how to approach the data access layer for a composable application? By composable application, I mean an application with ...
3
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1answer
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Is depending on lazy loading a code smell?

During my short experience with DDD I often find myself in the situation where I wished for some type of lazy loading mechanism to solve some dangerous cases where large nested data sets might be ...
3
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1answer
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CQRS + Event Sourcing: (is it correct that) Commands are generally communicated point-to-point, while Domain Events are communicated through pub/sub?

Didn't know how to shorten that title. I'm basically trying to wrap my head around the concept of CQRS ( http://en.wikipedia.org/wiki/Command-query_separation) and related concepts. Although CQRS ...
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DDD - Aggregate root with large number of children

I'll preface this question by saying I am relatively new to DDD so I may be making some fundamental mistakes here! I working on a project which involves the concepts of Accounts and Transactions (in ...
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3answers
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Enterprise application object oriented modeling for user and role

Generally in the Enterprise Applications like ERP or ERM, CRM, BP etc. we see two things a lot, one of them is Role and the other one is User. What happens is that in the real world we have some ...
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What is the best way to create DTOs from entities and update entities from DTOs in a layered architecture?

Option 1: At first I would make a call to my service layer, which served as an API for my core domain, to get a domain object or a list of domain objects and then pass them into the assembler which ...
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Which layers should reflect the domain language (if a domain language can strictly exist)?

This question relates to a one I asked earlier: http://stackoverflow.com/questions/5448574/under-what-conditions-could-we-justify-an-attempt-to-introduce-a-one-size-fits-al When re-reading ...