Granny's Programming Pearls
"inside of every large program is a small program struggling to get out"
The moose likes Object Relational Mapping and the fly likes Do I need O-R mapping for big project? Big Moose Saloon
  Search | Java FAQ | Recent Topics | Flagged Topics | Hot Topics | Zero Replies
Register / Login

Win a copy of Android Security Essentials Live Lessons this week in the Android forum!
JavaRanch » Java Forums » Databases » Object Relational Mapping
Bookmark "Do I need O-R mapping for big project?" Watch "Do I need O-R mapping for big project?" New topic

Do I need O-R mapping for big project?

Haulyn Jason
Ranch Hand

Joined: Jul 24, 2007
Posts: 37
I have a newbie's question about O-R mapping tools.

I am a java developer, and we always use jdbc as persistence layer. Just little time use IBatis as mapping tool.

Recently, we met a big project with is transactional based business system. There are much data need to solve. nearly 1000+ tables, DBAs say that they need to create about 2000+ views. OK, we need EJB3 ,but does we need JPA? I am not sure does JPA stable for so much data.

The problem I worried about is: I heard that linkedin has nothing O-R mapping, just jdbc directly. I am not sure does JPA stable for big project.


Mama always said, "Life is like a box of chocolates; you never know what you're gonna get. And then you have to get medieval on somebody's buttocks."
arulk pillai
Ranch Hand

Joined: May 31, 2007
Posts: 3219
O/R mapping is well suited for read--> modify --> write centric applications and not suited for write centric applications (i.e. batch processes with large data sets like 5000 rows or more) where data is seldom read. O/R mapping tools/frameworks allow you to model inheritance (Refer Q101 in Enterprise section), association and composition class relationships. O/R mapping tools work well in 80-90% of cases and use basic database features like stored procedures, triggers etc, when O/R mapping is not appropriate. Keep in mind that no one size fits all solution. Always validate your architectural design with a vertical slice and test for performance. Some times you have to handcraft your SQL and a good O/R mapping (aka ORM) tool/framework should allow that. O/R mapping tools/frameworks allow your application to be:

• Less verbose (e.g. transparent persistence , Object Oriented query language , transitive persistence etc)
• More portable (i.e. vendor independence due to multi dialect support )
• More maintainable (i.e. transparent persistence, inheritance mapping stategies, automatic dirty checking etc).

Java Interview Questions and Answers Blog | profile | Java Interview Books
Haulyn Jason
Ranch Hand

Joined: Jul 24, 2007
Posts: 37
ok, thanks arulk.

We are looking at JPA now. maybe it's a good idea to try it on a small project.

I agree. Here's the link:
subject: Do I need O-R mapping for big project?
Similar Threads
What are Spring alternatives when working with hibernate?
EJB and hibernate --same or different
To use ORM or not
OR, Performance
all this O/R questions