What questions/solutions arise when Domain-Driven Design is practised?
I have found getting a grasp of it somewhat difficult as new situations keep arising, so I am trying to compile a list of good resources/questions in one place to assist me and anyone alike me having trouble grasping/implementing it.
Here is one question I have encountered
Using The Repository Pattern, Is It Best To Save Parent and Child Objects Together Or Separately?
Some questions you can find searching for the tags domain-driven-design or ddd here in SO. The book from Eric Evans also give some good insight of some situations you may face.
One important note is ddd is like tests, in the aspect that it increases development time of new features, but increase quality (and consequently, reduces development time in the long term). You might need constant contact with domain experts, so you can refine the model each time an issue appears.
IMHO, the most important issue of ddd is having a good, meaningful domain. Most issues (though not all of them) root problem is poor understanding of the domain
It is difficult to say what issues are the most common, as for every domain is a different domain, with its own peculiarities...
In my experience, one of the top rules is "Build the Ubiquitous Language". Don't forget it, it's one of the most valuable aspects DDD provides to the development process. With a strong and shared ubiquitous language comes a meaningful domain and a shared vision of the problem that helps a lot.
My second rule is "The model is only one": don't model data, objects, classes, tables... just face the domain an model it, everything else must be derived naturally from this model, there is no gap between a UML class in the model and the Java (or the language you are using) class.