Tuesday, May 13, 2008

LINQ and Entity Framework Posts for 5/12/2008+

Note: This post is updated daily or more frequently, depending on the availability of new articles.

Brad Abrams and Omar Khan Podcast .NET 3.5 and VS 2008 SP1 Beta Features

.NET Rock's Brad Abrams and Omar Khan Announce .NET 3.5 SP1 and VS2008 SP1 podcase of May 13, 2008 carries this deck:

Brad Abrams and Omar Khan from Microsoft officially announce .NET 3.5 SP1 and Visual Studio 2008 SP1, and detail all the new features and improvements!

Added: May 13, 2008

David Hayden Posts Walkthroughs for the ASP.NET EntityDataSource and Dynamic Data Scaffolding

Dave's EntityDataSource Companion to ADO.NET Entity Data Model in Visual Studio 2008 SP1 and Dynamic Data Entities Websites - EntityDataSource and ASP.NET Website Scaffolding - Rapid Application Development ( RAD ) posts of May 13, 2008 are illustrated demonstrations of these new Entity Framework features for ASP.NET.

His ASP.NET Dynamic Data Websites Preview May 12 Refresh for Visual Studio 2008 SP1 on MSDN Code Gallery post of the same date notes that the Dynamic Data Website Wizard isn't included with VS 2008 SP1 Beta and must be downloaded from the MSDN Code Gallery. The Website Wizard continues to support LINQ to SQL only.

Added: May 13, 2008

ADO.NET Team Details VS 2008 SP1 Beta's Changes to Entity Framework

The ADO.NET team's What's New in the SP1 Beta? post of May 12, 2008 (9:30 PM) details changes to the following ADO.NET Entity Framework components:

  • EntityDataSource
  • Entity Designer (Breaking change to *.edmx files)
  • SQL 2008 Support (New datatypes)
  • Metadata
  • Query Improvements
  • EntityClient
  • Object Services
  • LINQ to Entities
  • EntityDataSource for ASP.NET
  • ASP.NET Dynamic Data Support

Added: May 13, 2008

Guy Burstein Demos LINQ to SQL SP1 Beta's SQL Server 2008 FileStream, Date, Time and DateTime2 Datatype Support

Guy's Visual Studio 2008 SP1: LINQ to SQL and FILESTREAM and Visual Studio 2008 SP1: LINQ to SQL with SQL Server 2008 Date Time Types posts of May 12, 2008 demonstrate LINQ to SQL's support for these new SQL Server data types.

Added: May 13, 2008

ADO.NET Entity Framework and ADO.NET Data Services Framework Updates Available for Download

Sam Druker announced Monday morning, May 12, 2008, in his Entity Framework & Data Services Available in VS2008 SP1 Beta post that the final beta before the RTM of the two frameworks is available for download:

The drop also adds SQL Server 2008's new date and time data types to LINQ to SQL.

The download page and Readmes are required reading.

Here's a link to the Original OakLeaf post, VS 2008 SP1/.NET 3.5 SP1 with ADO.NET Entity Framework and ADO.NET Data Services Framework, of May 12, 2008.

Scott Guthrie Provides Detailed Analysis of VS 2008 SP1 Beta Improvements

Scott's Visual Studio 2008 and .NET Framework 3.5 Service Pack 1 Beta, posted a few minutes after Sam's, includes these sections:

  • Important: SP1 Beta Installation Notes (Read before installing SP1)
  • Improvements for Web Development
  • Improvements for Client Development
  • Data Development Improvements
  • WCF Development Improvements
  • VB and C# Improvements

(This post is about 10-15 feet long.)

Update May 13, 2008: Microsoft Watcher Joe Wilcox wonders in his .NET 3.5 SP1 Beta Changes Your Expression column of May 12, 2008 "Who writes his blogs. Are they personally done?"

Beats me.

Joe also notes the strange dating of blog posts about .NET Framework SP1 Beta's incompatibility with the Expression product line.

Julie Lerman Outlines ADO.NET Entity Framework and ADO.NET Data Services Breaking Changes in SP1 Beta

Julie has two important posts that describe compatibility issues with earlier CTPs:

Stay Tuned: For another post after I've installed them and checked out their content.

Mike Flasko Details SP1 Beta Changes to ADO.NET Data Services Framework

Mike's ADO.NET Data Services Framework Beta 1 is Live! post to the Astoria Project blog augment's Julie's by describing these changes:

  • Assembly and namespace changes.
  • API Name Changes
  • Query Interceptor Changes.
  • Update Interceptor Changes.
  • Command line tool changes.
  • Tweaks to the ATOM payload format.

And these new features:

  • Batching
  • Optimistic Concurrency
  • New IUpdatable interface

David Ebbo Clarifies Status of ASP.NET Dynamic Data in VS 2008 SP1 Beta

His Clearing some confusion about Dynamic Data and VS SP1 Beta post recommends that you download the latest version of ASP.NET Dynamic Data from CodePlex for compatibility with VS 2008 SP1. The version included with the SP1 bits is considerably older than the CodePlex version, which was uploaded this morning.

Guy Burstein Posts Video Overview of the ASP.NET EntityDataSource Beta

Here's the description of Guy's Channel9 screencast, Overview of the EntityDataSource - The new ASP.Net Data Source, of May 12, 2008 as follows:

Guy Burstein talks about the EntityDataSource – the new ASP.Net Data Source that ships as part of the ADO.Net Entity Framework in Service Pack 1 [Beta] of Visual Studio 2008 and .Net Framework 3.5. In this video you will get a quick overview of the EntityDataSource and see some additional features you may want to explore later.

If you want a step by step walkthrough of using the EntityDataSource, here is where you can find:

Zlatko Michailov: The SP1 Beta-compatible Version of eSQLBlast is Available for Download

Zlatko's New version of eSqlBlast - compatible with .NET Framework 3.5 SP1 Beta post points to eSqlBlast (1.08.04.16) on the MSDN Code Gallery.

Soma Somasegar Describes the Two SP1 Betas

His Visual Studio 2008 and .NET FX 3.5 SP1 Beta available now post started the flood of articles and blog posts about the first (and only) beta of these two major service packs.

XML Tools Team Adds XML Data Explorer to VS 2008 SP1 Beta

According to the XML Team's New XSD Functionality in Visual Studio 2008 SP1 Beta 1 post of May 12, 2008 by Tim Lafferty, the XML Data Explorer, which previously was a separate CTP download, is now included in the VS 2008 SP1 Beta bits.

Added: May 13, 2008

Other Topics

A LINQ to the Past

MSDN Webcast: Introduction to New SQL Server Data Services: A Web-Based Data Storage in a Cloud (Level 200)

Fantasy Soccer - Part 4 - Architectural Overview

John Papa Tackles Entity Framework Questions in MSDN Magazine's May 2008 Issue

The "Entity Framework Q&A" DataPoints column of the May 2008 issue of MSDN Magazine discusses the pros and cons of three of the four Entity Framework query techniques:

  • EntityClient + Entity SQL (returns a DbDataReader)
  • Object Services + Entity SQL (returns strongly typed entities only)
  • Object Services + LINQ (returns strongly type entities or projections)

John doesn't discuss Object Services + QueryBuilder queries. He does discuss the differences between eager loading and explicit loading. (Entity Framework doesn't support automatic lazy loading as O/RM tools ordinarily define it. See post below.)

Added: May 13, 2008

Diego Vera: Network Roundtrips Should Not be Hidden from the Developer

Diego clarifies the reason that the ADO.NET Entity Framework doesn't provide O/RM tools' traditional lazy loading feature by default in an "Insights: Entity Framework Data Loading" sidebar to John Papa's "Entity Framework Q&A" DataPoints column and his Lazy loading in Entity Framework post of May 12, 2008: Omri Gazitt's contention in an Develop.com list server reply that "network roundtrips should not be hidden from the developer.

Added: May 13, 2008

Jaroslaw Kowalski Contributes Automatic Lazy Loading to Entity Framework

Jaroslaw's Transparent Lazy Loading for Entity Framework – part 1 and Transparent Lazy Loading for Entity Framework – part 2 posts of May 12, 2008 discuss the benefits and drawbacks of implementing automatic lazy loading to the Entity Framework by refactoring the entity classes. Jaroslaw says:

The implementation takes advantage of the fact that Entity Framework supports IPOCO. We introduce a base class called LazyEntityObject that all code-generated objects derive from, and that implements all interfaces required by Entity Framework (IEntityWithKey, IEntityWithChangeTracking, IEntityWithRelationships) and a new interface ILazyEntityObject. The implementation of these interfaces is done explicitly, which means that there is no single public API exposed on actual entity objects (not even EntityKey). ...

The first and foremost lesson learned is that it is quite possible to have transparent lazy loading working with Entity Framework. Being able to write your own entity classes (provided that they adhere to IPOCO specification) that add functionality under the hood opens up a whole new world of possibilities.

Watch for a subsequent post that "will explain the object type cache (for managing EntityKey to concrete type mapping) and introduce additional extension methods that make it possible to write LINQ and Entity SQL queries that return stubs of objects."

Source code compatible with VS 2008 SP1 Beta is available from the MSDN Code Gallery.

Added: May 13, 2008

Eric White to Integrate Microsoft XML Dialects with LINQ to XML

Eric was been the developer evangelist for Office Open XML (OOXML) during it's traumatic process of gaining approval as an ISO standard. He's now turning a more specialized task. He says:

About a year ago, I was talking to my (then) boss, and he asked me what I would really like to do in Microsoft. My response: LINQ to XML is one of the most powerful and enabling technologies that I have come across. There are many XML dialects used throughout the Microsoft stack (Open XML, CAML, XAML, XHTML, to name a few), and I wanted to work at the intersection of these technologies, using the power of LINQ to XML to connect them.

His SharePoint at the Intersection post of May 12, 2008 indicates he got what he wanted.

Added: May 13, 2008

Derek Whittaker's Mini-Series Compares LINQ to XML and XPath

Derek starts his XLinq'n in the new world - Data access comparisons with Xml/XPath series with the first post of May 12, 2008, which begins:

... XLinq is really no better per say than Xml/XPath.  However, what XLinq does bring to the table that Xml/XPath does not:

  • Does not need to use the XPath query syntax
  • Reads like English (mostly) when creating queries
  • Lower barrier to entry for someone new to Xml (my opinion)

In Part 1 of this little mini series we will examine some common data access scenario's and how XLinq's syntax compares to that of standard Xml/XPath access.

Added: May 13, 2008

2 comments:

Anonymous said...

I've been trying to get ADO.NET Data Services working against a SQL 2008 instance, but it seems like it can't handle certain tables in the AdventureWorks 2008 (like Person.Person for some reason). Some other tables work fine. I'm not seeing any discernable patterns yet. Not sure if I'm doing something wrong over here, but does anyone know if this is a known issue? Thanks.

--rj said...

Anon,

I haven't tried SQL Server 2008's AdventureWorks yet because I heard there was a problem between SP1 and AW2008. I've seen a couple of posts that the rumor was correct.

--rj