As a short follow-up on HTTP and optimistic concurrency , I wanted to touch on how OData deals with concurrency. The nice thing is that there is very little for me to write about. By and large, the OData protocol "piggy-backs" on the HTTP protocol...

Yes, our WCF Data Services blogging hero has gone and done it again - this time, the topic is expansions . Some of the highlights: What expansions look like for custom providers. Why there is nothing funny in the expression tree when using LINQ to Objects...

I was recently talking about optimistic and pessimistic concurrency . That got me thinking about one of the most popular protocols around: HTTP. While HTTP doesn't refer to this in as many words, it does in fact have support for an optimistic concurrency...

In case you've missed them, there are two walkthroughs that have been recently posted on some of the EF CTP4 shininess. Code First . Walks you through describing a model with classes, touching them up with a fluent API through a builder or configurations...

I remember that this was a tricky thing for me to understand and remember when I first got started with databases, so I thought I might help someone out by explaining these in a simple way. Optimistic and pessimistic locking (or concurrency control) are...

A few days ago I came upon a question about how decimal values are encoded in JSON payload in an OData response. The value was in quotes rather than as a numeric literal, so a script running in a browser found a string where the developer thought a number...

Continuing from yesterday's post , we'll use XPathNavigator.Evaluate to sketch some helper functions that can be used to test components. For example, if we're testing the results of a transformation or of some custom XML from a REST-ful service, we would...

Today I simply want to call out a somewhat obscure but very useful method: XPathNavigator.Evaluate . Many users of XML components are familiar with APIs such as SelectNodes or SelectSingleNodes . These are declared on the XmlNode class, and are thus available...

In case you missed it, you should read Vitek's post on Projection Data Service Expressions . Here you will get not just the basics of his this works, but also details as to: Why we may query for more properties than those strictly projected. Why ProjectedWrappers...

Today, just a historical note on why these methods are named as they are. What we needed when designing this a few years ago was a way to set at a basic level what kind of access we would provide from the service, preferably in a uniform manner. There...

Today, a simple link to OData, O How I Love Thee , with a nice review of how OData, WCF Data Services, ADO.NET Entity Framework and jQuery can all be better together. Enjoy!

So I wrote a bit last week about the importance of not lying through your APIs , but I didn't offer any examples on how to improve the examples I gave. Let's take one at a time and consider how they might get improved. The first case we had was the mis...

As a general word of warning to the world, it's good to be careful about how far into the future you queue up blog posts if you're in the habit of doing so. For example, if you have a post that references something you think might be current events like...

So, the OData Protocol talks about custom query options , but how exactly do you use them from the WCF Data Services client? If you've used service operations at all, you already know the answer: use the AddQueryOption method. There is a subtle difference...

Today I want to talk about how InfoPath and SharePoint allow non-developers to develop some very sophisticated systems. Someone I know was just stepping into a new job, a startup-like organization currently in the process of defining many of their internal...

Today is the last post from a couple of design thoughts I've been writing down, and it addressed what happens with components over time. The natural tendency of systems is to gain more capabilities over time. The path of least resistance is often to extend...

As a follow-up from yesterday's post about not lying , I wanted to discuss a bit some thoughts on abstraction levels. At first, it would appear that high-level methods lie a lot. When you ask a SqlConnection object to Open, it actually does a bunch of...