I was pretty impressed with the LightSpeed O/R Mapper when it was first released, but the new Visual Studio 2008 Integrated Design Surface in LightSpeed 2.0 makes it really easy to develop and maintain domain models from a database. Just like with LINQ To SQL, you can drag and drop your tables from the Server Explorer onto the LightSpeed Visual Designer and have LightSpeed generate a model for you under the covers.
Even though LightSpeed 2.0 feels a bit slow in generating the initial model when you drag a number of tables onto the surface, it is a real gem for kickstarting your development when you already have a database. I read in the forums that they have better optimized this process in the nightly builds and we will probably see performance improvements in a maintenance release in the near future.
What makes the Lightspeed 2.0 Visual Designer stand out over the LINQ To SQL Designer is that you have database Schema Round-Trip Updates with LightSpeed 2.0. Just right-click the design surface and either choose to update the model from the database or update the database from the model. In real-world development the database schema / model always changes over time and the fact that you can synchronize your model and database schema is a huge benefit for application maintainability.
You also have a LightSpeed Model Explorer that allows you to view your Entities, Entity Properties, Aggregations, and Validations. Once again, this is very, very slick and makes it easy to adjust the model to the needs of your application. The validations shown in the image below were automatically created based on the database schema. In this case CategoryName cannot be null and has a maximum length of 15 characters. You can of course add other validations either via the Lightspeed Model Explorer or the Properties Window.
In addition to the LightSpeed Visual Designer you also get the power of LINQ in Lightspeed 2.0. Using the strongly-typed UnitOfWork, we can query for all the Beverages in the Products Table of Northwind using a simple query expression that we have grown so very fond of:
using (var unitOfWork = context.CreateUnitOfWork())
{
var beverages =
from p in unitOfWork.Products
where p.Category.CategoryName == "Beverages"
orderby p.ProductName
select p;
foreach (var product in beverages)
Console.WriteLine(product.ProductName);
}
Make sure you read about the limitations to the LINQ Provider in LightSpeed as mentioned in the documentation. There appear to be a couple of things it doesn't support, but my guess is that they with either be supported in the future or you can find a way around them without using LINQ.
Overall, I would say that LightSpeed is a replacement for LINQ To SQL. Realizing Visual Studio 2008 SP1 will be offering some new technologies, I would love to see a few enhancements to LightSpeed -
- Support for Stored Procedures
- A DataSource Control
- ASP.NET Dynamic Data Support
- ADO.NET Data Services Support
If you are using LINQ To SQL now for your O/R Mapping needs, I recommend checking out LightSpeed.