Debugging NHibernate: session management

Invalid session management is one of the common problems when using NHibernate and can lead to severe issues such as memory leaks or data inconsistency. In this post I am going to show you how to eliminate those pitfalls using the Visual Studio debugger. We will step through the process of opening and closing the session. We will also have a look at its properties in order to check if entities are correctly persisted. Let’s start then from breaking into the session open event.

Debugging NHibernate: prepare symbol files

To be able to debug the NHibernate source code the debugger must know how to find it. If you are using the 3.0.0 version of NHibernate you may use http://www.symbolsource.org configuring Visual Studio to use their symbol store. If your NHibernate version is different you need to either compile NHibernate on your own and reference the produced binaries in your application build process or make use of the sourcepack script. Here I will describe the second approach (especially because I’m the author of the sourcepack and I need to advertise it somehow ;)).

Take advantage of Reference Paths in Visual Studio and debug locally referenced libraries

Are you using NHibernate or other open-source library in your project? I’m pretty sure that you are. Have you ever wondered what’s happening “under the cover” when you call Session.Get or perform a query? You probably did. The problem is that usually all the external assemblies are stored in one directory (libs, packages, reflibs etc.) with no symbol files or sources. In this post I would like to show you how you can benefit from project’s ReferencePath property and debug the source code of your libraries at any time you want.

Changelog for domain objects

In this post I would like to present you a simple way to implement changelog system for database objects using NHibernate session interceptor and database triggers. This system will inform which rows were created, deleted and which columns were updated and what were their previous values.

How to store database constants in the application code?

If you are a database application developer you often face the problem of using database constants in your application code. I would like to present you a way how to use such constants and avoid hard-coding data-table primary key values.