I’ve been meaning for a while to start up a series of posts that covers building LINQ providers using IQueryable. People have been asking me advice on doing this for quite some time now, whether through internal Microsoft email or questions on the forums or by cracking the encryption and mailing me directly. Of course, I’ve mostly replied with “I’m working on a sample that will show you everything” letting them know that soon all will be revealed. However, instead of just posting a full sample here I felt it prudent to go step by step so I can actual dive deep and explain everything that is going on instead of just dumping it all in your lap and letting you find your own way. ...

Now that LINQ is out the door, so to speak, I can start focusing my efforts on the next next technology here at Microsoft. Ever since I joined up with the C# team nearly two years ago I’ve been frustrated by my inability to wax poetic about all the goodness...

It's late, do you know where your coder is? Really, it's a very good question. You think your spouse is sleeping next to you at night. They are not. They are awake, bleary, weary and barely lucid, secretly feeding their addiction. Yes, it is sad and...

I am going to tell you something that will disturb you. You might laugh, but it will be a cold uncertain laugh that will haunt you as you read on, because somewhere deep down you'll know it to be true. You might brush it off, get on with your day, yet sometime later, a week or a year, it will seep back in and unsettle you to the core. From that moment on you will be changed. You will think different, act different and will fundamentally be different. So take a moment to prepare yourself now, breath deeply, clear your mind and open up to the possibility that building software is hard. ...

So, again you thought I was done with this series, that I've given up and moved on to greener pastures. You think that since Select works wonderfully that that's all you need to know to make your own IQueryable provider? Ha! There's loads more to know. And, by the way, Select is still broken. ...

Now, that I’ve laid the groundwork defining a reusable version of IQueryable and IQueryProvider, namely Query and QueryProvider, I’m going to build a provider that actually does something. As I said before, what a query provider really does is execute a little bit of ‘code’ defined as an expression tree instead of actual IL. Of course, it does not actually have to execute it in the traditional sense. For example, LINQ to SQL translates the query expression into SQL and sends it to the server to execute it. ...

A new update to LINQ preview is available at MSDN site. What's the coolest new feature? IMHO, its IQueryable<T>. DLINQ's query mechanism has been generalized and available for all to use as part of System.Query. It implements the Standard...

Over the past four parts of this series I have constructed a working LINQ IQueryable provider that targets ADO and SQL and has so far been able to translate both Queryable.Where and Queryable.Select standard query operators. Yet, as big of an accomplishment that has been there are still a few gaping holes and I’m not talking about other missing operators like OrderBy and Join. I’m talking about huge conceptual gaffs that will bite anyone that strays from my oh-so-ideally crafted demo queries. ...

LINQ to SQL, possibly Microsoft’s first OR/M to actually ship in ten years of trying, was never even supposed to exist. ...

Everywhere I turn, all I read about is dynamic languages. Apparently, there is a small yet growing contingent of programmers that think dynamic is the only way to go. These guys are frustrated with the shackles of static type systems that force them to...