But there are a couple of things though:

1. Quality of SQL
If the SQL is, basically, crap, then it’s not going to work very well. Possibly, if when using ObjectSpaces, it creates SPs (when using MSSQL 200/Yukon) and you can tweak them, then it might not be too important. But then again, it does kinda defy the point of it.

2. Other DataSources
Obviously, engineering ObjectSpaces to work best with their own RDBMS’ is the smarter thing to do. But making it only available to MSSQL 2000/Yukon could be potentially harmful, even if they added Access. In my work, we opted for MySQL. There isn’t much of a performance increase in using MSSQL to justify the outlay for it, and when upgrading to ASP.NET Whidbey and not having the option to use ObjectSpaces would make me cry myself to sleep! Not only ASP.NET though, internally, we’ve written a lot of apps that use MySQL as its datasource and would have a heavy impact. More crying myself to sleep!

3. Performance Overhead
I started life writing code as a web developer (unless you old 680×0 assembly and AMOS on my lovely Amiga!) and performance is always the first consideration (moving to Windows development was strange on this aspect, but it proved hand, especially PDA development!). If the overhead added by using ObjectSpaces is too much, then it’s not going to be a viable option for web development (reading those XML files can’t be resource friendly!).

That’s about it really… bear in mind that I haven’t actually used ObjectSpaces yet, so my comments might be total crap, and also that ObjectSpaces is far from complete.

:)

Microsoft’s Whidbey release only supports Microsoft databases, and at present Microsoft have no plans to support other database vendors, though have developed the technology to open it up in the future. Read Andrew Conrad’s unofficial-official position on this.

Microsoft themselves state in their literature for ObjectSpaces, use them if “Raw performance is not your main goal”. That said, overheads of producing your own business object “mappings” will narrow the performance gap too. I’ve used ObjectSpaces in Whidbey, and there is a definite pause when streaming very large data sets with the ObjectReader vs. SqlDataReader…

Microsoft have entered this field rather late in my mind…if they’d had this available when .NET v.1 shipped, it would be something to get excited about. But its all here already, tested, examined, and available. Try Entity Broker, or Paul Wilsons ORMApper which is based on the ObjectSpaces syntax and supports MySQL.

The concepts are still relevant however, but I will get on to updating the code. Thanks for the pointer.