Deep Data - Introduction of new logical layers?

vdhant posted on Thursday, July 31, 2008

Hi Rocky
I have been looking through Deep Data a bit lately and it is exactly what I was after. Its a great sample and I really appreciate the time that originally went into it creating it.

One thing I was wondering thoug, would you say that with these approaches (practically the separate DAL using the DTO's) any new logical layers are introduced around the Data Access layer or would you say that these are simply a part of the data access layer. Also depending on your answer in this case are the DataPortal_xyz methods still Data Access methods (I would be guessing that they are), but I could also see that they become business logic methods that simply specialise in accessing the Data Access layer.

As a side point to this post, I think it would be worthwhile to mention in passing in your new book that these are other approaches that can be used when it comes to implementing ones data layer. As far as I can remember I don’t think that this was mentioned in the book and with the way you talk about integrating the data access methods into the business object itself, it could be taken as the only way of doing data access. I know this is never the case, but you do make a very strong argument for putting the data access in the business object and you never hint at any other approaches. Just a thought.

Cheers
Anthony

RockfordLhotka replied on Thursday, July 31, 2008

The 2008 book will have a chapter just on data access (separate from the data portal) in an effort to address some these questions. But at 25-30 pages per chapter I surely won't cover all the options in any detail.

I do consider the ideas of a DAL factory, DAL locator, DAL router, DAL instance, etc. all to be part of the logical data access layer.

Just like I consider Controller, View, Presenter, UI coordinator, code-behind, UI controls, UI helpers, LINQ queries to do sorts/filters and all sorts of related things as being part of the logical UI layer.