Sunday, January 09, 2005

Challenging traditional 3-layer/3-tier view of application

I just came across an interesting article by Rockford Lhotka at TheServerSide.net. In this article titled "The Fallacy of the Data Layer" Mr Lhotka insists that in a service oriented world we should not view data access as a layer but rather as a service. He quite rightly points that Data Sources usually are not maintained/owned exclusively by the application(service) (e.g think of SQL Server or any other data store) and hence they can not be thought of as an application layer. I believe he makes a valid point and it should be taken. So, next time in Service Oriented Context, don't think/call ur data access code a "layer", rather call it a "service".

1 comment:

Javier Luna said...

I believe that any DataLayer must be a simple code block, that they allow operations against DB.

That code block would not have to know on the Business Entities. Single to specialize it is to execute the operations (Store Procedures and SQL Sentences) against the engine DB (SQL, Oracle, DB2, etc.), with which this setting.

Finally, I invite to you to download the DataLayer.Primitives Public Version.

This is very cool Data Layer :)

DataLayer.Primitives - Readme!
http://forums.microsoft.com/msdn/ShowPost.aspx?PostID=1389

Cheers,

Javier Luna
http://guydotnetxmlwebservices.blogspot.com/