These days I am in a fix over use of O/R Mapping and Domain Objects and how do they fit into Enterprise Scale Application development scenario. When I asked this thing to Clemens Vasters, he said the following things:-

 

you might want to consider the following questions:

 

a)       How effective is O/R mapping when you don’t look at single objects but rather need to fetch sets of data (assume the price history for a stock) based on certain criteria such as a certain time period?

b)      How do you integrate with transactions and how do you assure that you are in control of the order and locking hints of insert/update operations to minimize deadlocks/lock contention?

c)       How tight is the coupling between your relational model and your objects? Can you change the table layout and indexing of the data store flexibly as your data volumes change?

d)      Can you effectively hide the database detail implementation and provide a “secure gateway” into the database using a layer of stored procedures and views?

e)       How tight is the coupling between your business code and the underlying data store technology? Are you bound to a certain database product or even product version?

f)        What is the net efficiency gain that O/R mapping gives you in development? Is it actually making developers more productive in creating *and maintaining* your software or is it merely “more elegant”?

 

I am not sure that O/R mapping technology scores very favorably in many of those considerations.

 

Best Regards

Clemens Vasters

 

SO things arent getting clearer here . And I am back to my drawing board and scratching my head !