Saturday, 22 January 2011

NHibernate

Name	NHibernate
Latest release version	3.0.0
Latest release date
Latest preview version	3.0.0 Beta 2
Latest preview date
Operating system	Cross-platform
Platform	.NET 1.1 or 2.0 and Mono
Programming language	C#
Genre	Object-relational mapping
License	GNU Lesser General Public License
Website	http://www.nhforge.org/

NHibernate is an Object-relational mapping (ORM) solution for the Microsoft .NET platform: it provides a framework for mapping an object-oriented domain model to a traditional relational database. Its purpose is to relieve the developer from a significant portion of relational data persistence-related programming tasks.

NHibernate is free as open source software that is distributed under the GNU Lesser General Public License.

NHibernate is a port of the popular Java O/R mapper Hibernate to .NET.

A partial implementation of a LINQ provider is available for 2.1. A new LINQ provider using the AST parser built for NHibernate's HQL (Hibernate Query Language) engine is in development for version 3.0 of NHibernate. It is currently available for preview in NHibernate 3.0.0.Alpha2 (at 2010-08-15)

Feature summary

NHibernate's primary feature is mapping from .NET classes to database tables (and from CLR data types to SQL data types). NHibernate also provides data query and retrieval facilities. NHibernate generates the SQL commands and relieves the developer from manual data set handling and object conversion, keeping the application portable to most SQL databases, with database portability delivered at very little performance overhead.

NHibernate provides transparent persistence for Plain Old CLR Objects (POCOs). The only strict requirement for a persistent class is a no-argument constructor, which does not have to be public. (Proper behavior in some applications also requires special attention to the Equals() and GetHashCode() methods.)

History

NHibernate was started by Tom Barrett, and later picked up by Mike Doerfler and Peter Smulovics. At the end of 2005, JBoss, Inc. (now part of Red Hat) hired Sergey Koshcheyev, the then lead developer of NHibernate, to work full-time on its future versions. At the end of 2006 JBoss stopped the support to this project; it is now entirely developed and led by the community.

Version 1.0 mirrored the feature set of Hibernate 2.1, as well as a number of features from Hibernate 3.

NHibernate 1.2.1, released in November 2007, introduced many more features from Hibernate 3 and support for .NET 2.0, stored procedures, generics, and nullable types.

NHibernate 2.0 was released August 23, 2008. It is comparable to Hibernate 3.2 in terms of features. With the version 2.0 release, NHibernate dropped support for .NET 1.1.

NHibernate 2.1 was released July 17, 2009.

NHibernate 3.0 was released on December 04, 2010 and is the first version to use .NET 3.5.

Contributions

As open source software, NHibernate has received many contributions from its users. Most of them are directly integrated as internal features. Others are provided by the users as utilities and documentation.

Implementation of LINQ has allowed Language Integrated Query use with NHibernate.

References

Bibliography

External links

NHibernate Homepage

NHibernate Sourceforge Summary

NHibernate overview by Justin Gehtland Part 2

Category:.NET programming tools Category:.Net Object-relational mapping tools

This text is licensed under the Creative Commons CC-BY-SA License. This text was originally published on Wikipedia and was developed by the Wikipedia community.