DotNetKicks.com - Stories tagged with NHIbernate

NHibernate - <natural-id/>

Thu, 25 Jun 2009 17:38:42 GMT

A natural id is a way to refer to a unique field of an object as a substitute of the real entity identifier. A good (and typical) example of that would be with the User entity. We have the user name and the user id, both are unique, but the user id is usually something that is generated by our application and has no relation to the a human being. In other words, user #123814 doesn't mean anything to me, while user 'ayende' has a meaning to us.

Book review: NHibernate in Action

Mon, 15 Jun 2009 07:29:35 GMT

In this post I review the book NHibernate in Action from Manning Publications. As far as I know this is the only book that solely covers the Object/Relational Mapper NHibernate.

NHibernate - Beware of inadvisably applied caching strategies

Thu, 04 Jun 2009 06:09:30 GMT

One of the usual approaches for performance problems with most applications is to just throw caching on the problem until it goes away. NHibernate supports a very sophisticated caching mechanism, but, by default, it is disabled. Not only that, but there are multiple levels of opt ins that you have to explicitly state before you can benefit from caching. The answer is quite simple, caching is an incredibly sensitive topic, involving such things as data freshness, target size, repetitive requests, etc. Each and every time I have seen caching used as a hammer, it ended up in tears, with a lot of micro management of the cache and quite a bit of frustration.

Mapping a Twitter like domain with Fluent NHibernate

Sun, 24 May 2009 20:07:34 GMT

I'm currently learning NHibernate, and one of the best ways to learn is to blog about it :) Since I'm not a big fan of XML files, I also wanted to use Fluent NHibernate to do the mapping. As an example I will use a social messaging domain, similar to Twitter. I will also use a Top-down approach, starting with the domain model, writing the mapping, and finally creating the database schema using the SchemaExport class in NHibernate.

Logging NHibernate SQL with log4net in ASP.NET

Sun, 24 May 2009 03:39:24 GMT

Have you ever wondered how to log the SQL generated by NHibernate? This post tries to exemplify just that. NHibernate uses HQL to leverage its expressiveness to the developer, but behind the scenes there is an engine that transforms the HQL into pure SQL that is executed against the database. This SQL can be logged so that you can see its...

NHibernate guides

Thu, 07 May 2009 19:50:52 GMT

I made compilation of various NHibernate guides, help topics, walktroughts, . . Main source is Ayende and Fabio Maulo guides and posts which I find most useful. I hope you'll find this compilation useful either.

NHibernate: Transparent pre generation of lazy loading proxies in VS

Tue, 05 May 2009 19:55:36 GMT

Pre generate NHibernate lazy loading proxies with minimal changes to project, build and deploy configuration, to make whole process of proxies pre generation transparent as much as possible.

ActiveRecord, Firebird and Guid Primary Keys

Tue, 28 Apr 2009 17:37:19 GMT

I like to use the Guid values as Primary Keys, because I do a lot of data synchronization and sometimes I need to know the ID value before saving the record into the database. Here is a good article about using the Guid as Primary Key.

Simple example of using a Subquery in NHibernate when using ICriteria

Tue, 07 Apr 2009 07:04:07 GMT

Here is a simple, straight forward way to create a subquery with NHibernate.

Introduction to NHibernate, pt.5 - Mapping Value Types

Sun, 22 Mar 2009 18:55:58 GMT

In this post author mentions about mapping value types in nhibernate.

NHibernate POID Generators revealed

Sun, 22 Mar 2009 02:31:02 GMT

In this post author shows some differences among identity generators for NHibernate.

Fluent NHibernate new style mappings - powerful semantics

Fri, 20 Mar 2009 01:01:06 GMT

So today I updated to the latest build of Fluent NHibernate. As any of you who might have done the same have discovered there are some breaking changes. I wasn't sure I liked the new class based conventions at first, especially since it wasn't clear at first how to tackle altering my mappings. Then it dawned on me how powerful the conventions would end up being while also promoting DRY.

Verifying that that your data is Eagerly loaded in NHibernate

Fri, 06 Mar 2009 22:10:51 GMT

Taking a look at how you can use the NHibernateUtil to ensure that your eager loaded data was actually eagerly loaded.

Eager loading a One-to-Many collection w/ NHibernate

Fri, 06 Mar 2009 22:01:07 GMT

A quick overview on how to resolve a common one-to-many issue with eager loading when you get multiple records back from the child collection.

Learning to use Fluent NHibernate: Mapping with Composite Keys

Wed, 04 Mar 2009 04:01:03 GMT

In this episode we will continue our short series on how to use the FluentNHibernate library to create you NHibernate mapping files. We will walk you though how to create your mappings for tables which have Composite Keys. This is NOT meant to teach you how to use the NHibernate OR/M

NH2.1.0: generators behavior explained

Fri, 27 Feb 2009 06:16:03 GMT

Diving in generators behavior. In the last year we saw an increment of NHibernate's users and sometimes they are ignoring some facts, by the way I'm hoping this post will be useful to "old" users too. I will try to show you what happen behind the scene and hopefully this will be one of the bases, of your decision, when you must choose a POID generator strategy....

Troubleshooting common mapping bugs with NHibernate

Mon, 23 Feb 2009 21:04:04 GMT

Explore 7 common errors encountered while working with NHibernate Mappings, looking at their causes and how to resolve them

Diving in NHibernate.Validator

Thu, 26 Feb 2009 18:16:02 GMT

Surfing in the NET, to find some NHibernate.Validator (NHV) example, I saw that there are various things not so clear about how NHV is working. In this post I'll try to give you a more deep explication....

Improve your NHibernating with NHProf

Wed, 18 Feb 2009 20:31:03 GMT

A short review of experience using Hibernate profiling/debugging tool NHProf.

Changing the default conversation factory for uNHAddins

Fri, 13 Feb 2009 13:29:22 GMT

Advanced usage of uNHAddins conversation for NHibernate

Learning to use Fluent NHibernate: Getting started w/ your 1st Mapping

Thu, 05 Feb 2009 23:31:14 GMT

Learning to use Fluent NHibernate: Getting started w/ your first mappings

Mapping a One-To-Many Relationship with Fluent-NHibernate w/ Composite

Sat, 31 Jan 2009 22:22:23 GMT

Taking a look at how to setup the NHibernate mappings using Fluent-NHibernate when you have a One-To-Many relationship which uses composite-id's.

Mapping a One-To-Many Relationship with Fluent-NHibernate w/ Composite

Sat, 31 Jan 2009 22:22:23 GMT

Taking a look at how to setup the NHibernate mappings using Fluent-NHibernate when you have a One-To-Many relationship which uses composite-id's.

Many-to-One mapping throwing a ObjectNotFoundException, and how to fix

Thu, 29 Jan 2009 21:50:17 GMT

A simple how-to on how to get around the pesky ObjectNotFoundException when dealing with collections in NHibernate

NHibernate Query Analyzer + ActiveRecord

Mon, 19 Jan 2009 11:27:11 GMT

NHibernate Query Analyzer (NHQA) helps a lot while working in a .NET project with a relational database that makes use of NHibernate as the persistence manager. I was having a problem getting NHQA to work with a business data layer constructed with the help of ActiveRecord - I searched the Internet for a path that would led me in the right direction and after solving small errors I got NHQA working with a proper configuration file. In this post you'll find the content of the file so that you can get a sense of what must be done with the initial configuration of NHQA.