Object Relational Mapping

[SteveBarnes]

I'm interested to know if anyone has played in this space. If you generate classes etc out of Visio, the mapping to the database is still an issue, much like in J2EE.

Is there an object/relational mapping tool available or being built for .NET? How does this fit with the prevalent architectural patterns in .NET?

Best regards, Steve Barnes
Architect

Brisbane, Australia

 

[chiph]

Steve -

Rational has their XDE product, which I think does OO to relational mapping. It's not cheap - around 3500USD per license if I recall.

http://www.rational.com/products/xde/index.jsp

Chip H.

 

[SteveBarnes]

Unfortunately XDE doesn't solve this problem either! The Java J2EE space is filling with these products, but not the .NET space. Among the reasons for Microsoft lagging are:
* Microsoft uses predominantly table based rather than domain (object) based patterns. The recordset is their main medium of data transport.
* There is not the open user development community out there to drive the domain based patterns into the .NET space yet. Visio may generate objects for you, but is almost against the grain for .NET, as it leaves you disconnected from the DB. It seems object factories would be better. refer Martin Fowler's work on patterns at martinfowler.com (

http://www.martinfowler.com/isa/).

All the best, Steve Barnes
Software Architect

Brisbane, Australia

 

[chiph]

I've been mostly doing what Martin refers to as a TableDataGateway (I just call it an I/O class). It works, up to a certain level of complexity. A single parent-child relationship is fine (Invoice <- InvoiceItem), but three-level relationships (CustomerInvoice <- Invoice <- InvoiceItem) become unwieldy.

Chip H.