Filtered association loading and re-creating an entity graph across a web service boundary…

Roger Jennings, in his recent post Controlling the Depth and Order of EntitySets for 1:Many Associations, makes a case for the importance of two features in an O/RM if you want to build data-centric web services using it: the ability to do a filtered relationship navigation, and the ability to either serialize a graph or at least…

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So they’re hard, but what if I need them…

In my last post I started a survey of problems with building data-centric web services.  When we left our hero (you my intrepid entity framework programmer) things were looking pretty bleak.  So far we’ve talked about the challenges.  Now let’s talk about some possible approaches for dealing with those challenges.   1)      The traditional SOA…

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Why are data-centric web services so hard anyway?

Let’s say I’ve got a database and even some decent technology to help me to handle persistence between that database and my business objects which create a nice abstraction over the data and enforce validation.  I’ve also got clients (maybe rich apps, maybe web apps, maybe some business integration batch process) which live in a…

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DataContract Serialization, Entity Framework and "Known Types"

One of the challenges encountered when using DataContract serialization (the default for WCF web services) is support for polymorphic types.  If you have a type hierarchy (eg. class A and class B which inherits from A) and each class in the hierarchy has DataContract/DataMember attritibutes, then you can create service methods that take those types…

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Computing an Original Value Graph

In a previous post I shared some code which can be used to compute an original value version of an object using the information stored in ObjectStateManager, and in this post I gave some background about how the state manager and the relationship manager work together to track relationship information.  Now let’s see if we…

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How To: use your existing CSDL/MSL/SSDL files in the Entity Designer CTP2

Sanjay Nagamangalam who is the lead PM for the Entity Designer wrote up this great how-to for taking existing EF metadata files and bootstrapping them into the designer.  Thanks Sanjay! How To: use your existing CSDL/MSL/SSDL files in the Entity Designer CTP2   The ADO.NET Entity Designer stores EF metadata artifacts (CSDL/MSL/SSDL content) in a  .edmx…

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EF Beta 3 is finally available!

It has been a long time in coming (especially for those of you who have installed VS 2008 RTM and then been frustrated about the inability of beta 2 to work with it), but beta 3 of the Entity Framework and CTP 2 of the EF Designer are finally available!  There are four steps to…

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December 1 and Winter Has Arrived in Redmond

While there are places nearby that do get a lot of snow, normally weather is pretty mild around here.  This year, though, December brought with it snow for real (not to mention power outages and other adventures)…   Of course now that the power outages have past so that I can actually get this post…

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Concepts Part II: Relationships

Recently I shared this post which has some code that demonstrates how to create an object matching the original state of an entity tracked in the ObjectStateManager.   While this is useful, it’s more interesting to create the  entire original value graph.  As I thought about how to explain that code, it seemed pretty obvious to…

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Me too…

OK.  So I just read this post on Julie Lerman’s blog, and my reaction is “me too, me too.” What I mean to say is that I’d sure like to hear what things are causing people to dislike the EF or be afraid of it or whatever, because I’m in a position to do something…

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