When we talk about Object Relational Mapping Frameworks or ORM frameworks we’re talking about mapping relational data to an object-oriented programming language.
The ORM framework will hold features such as support for JPA (Java Persistency API); database access control mechanisms such as JNDI, JTA, JDBC; distributed processes, 2 phase commit, etc.
So on the hand you need to be able to map your relational data to object relational data and on the other hand you need to have a clear view on your persistency layer.
How are you going to manage the different transactions in your application, how are you going to deal with distributed transactions, etc.
In Oracle Toplink 11g or the Oracle Toplink Grid you have the marriage of the ORM Framework and Coherence which offers you the power to control your transaction based application.
In other words you can hand over the persistency management to coherence instead of giving your architect and developers the burden of solving this puzzle themselves.
When using Toplink Grid you can choose to have Coherence manage the persisting of new and modified Entities. This integrated solution involves a layer between JPA and the data store where the grid can be leveraged to scaling beyond the database bound operations.
In other words you’re application doesn’t need to wait for your database transaction to return an answer before it can proceed. Using asynchronous processing in your application will be a huge improvement for the end users’ experience and will leave the responsability to the JPA layer were it needs to reside.
For more information regarding the Toplink Grid, read the following article.
This is a whole new way of thinking about persistency and data centric web applications which will have a great influence on as well the software architects as the end users’ experience.
Will we still have the so called ‘slow java web apps’ versus ‘data centric web apps’ which can lead to huge discussions amongst ‘client-server developers’ and ‘web developers’ ?