Hey all - I'm trying to understand the basic architecture of DNN and am wondering if I am off base with how I understand the data provider model to work.  From what I can tell EACH module has a specific data provider implementation in addition to the abstract dataprovider class.  Unless I'm missing something this seems really messed up - For instance I would LOVE it if DNN ran on MySql but it doesn't - so if someone wants to run a DNN site on MySQL, they would have to add MySql data providers in all modules?   If this is the case, this just seems horribly wrong - it would be MUCH better if we had the data providers centralized and then all modules would point to a generic common abstract class - so one could add/change data providers on the entire system without having to modify or add code to existing modules.  The way it stands right now, it seems like it'll take a hell of a lot of effort to get another provider simply because one would have to touch all the core modules.  Am I missing something?

Bob

Bob,

I think you are right ON base.  There is lot done to separate and abstract the data access.  That works great.  It does add complexity, but with templates and code generators it really isn't all that hard.

I don't see how Michael Washington's description of the DAL and DAL+ explain how it is possible to have modules that don't have separate code for each dataprovider.  Granted that code will not have to be sprinkled throughout the BLL code.  But at some point it eventually calls a stored procedure.  The two big problems are:

1.  What happens with databases that don't support stored procedures?

2.  You have to write those stored procedures for each provider for your specific module? 

so if I want to use an oracle provider then every module I use has to come with an install, that will create the tables and stored procedures necessary to add update, get... the data for that module. 

To really make it dataprovider swappable then the install would have to take some sort of generic stored procedure definitions and then the provider would translate those into the form required for it's mother database.  Then the modules don't need to know anything about the database.  All they need to know is what the dataprovider needs to get its job (of talking to the database) done.

Then ya really got somethin.

I'm with you Bob.

mj 

see:

Converting the DotNetNuke® Survey module to use the DAL+ (in VB and C#)