WinFS and the Language Integrated Query (LINQ) Project

Microsoft's pre-PDC release to MSDN subscribers of WinFS Beta 1 bits was a surprise to the trade press, as well as most .NET developers. InfoWorld's "Surprise! Microsoft's WinFS beta arrives" article by Eric Knorr appeared on August 31, 2005 and briefly describes the first WinFS tools for developers. Paul Thurrott's "Windows Storage Foundation (WinFS) Preview" provides a historical context for WinFS—begining with the Object File System (OFS, codenamed Cairo) that Microsoft once promised for Windows NT. Quentin Clark, Microsoft's director of program management for WinFS, briefly describes reasons for early release of the WinFS Beta and the relationship between WinFS and IQF in his initial post—Shipping WinFS Beta 1—on the WinFS team's blog. Here's the early version of the WinFS/LINQ story from Quentin's post:

Another piece of feedback was concerns over the WinFS api’s being a different data access pattern than our existing managed code data acess APIs. Further, that our APIs were not aligned with broader data platform needs like OR mapping. This was a big one, and as you explore the SDK and the APIs, you will see the beginnings of how we will be addressing this. We are in the process of building-out the next version of ADO.NET to have new features that provide a data model, object-relational mapping, and flexible query infrastructure. The new data model is about entities, and the WinFS data model of Item types is built on that model. Looking through our SDK and code samples you will see how Items are composed of underlying entities. OR mapping is a big requirement - WinFS is a very prescribed mapping (defining a type in WinFS generates both the underlying storage schema and the partial class to program to that type). But the real-world has lots of requirements for flexible mapping – to existing data, to existing objects, etc. On query, many of you have heard about Anders Hejlsberg’s work on Language Integrated Query – and the new ADO.NET functionality will plug directly underneath so that you can use the new query patterns on any entity data, including of course now WinFS Items.

Thus, it's likely that you'll be able to integrate WinFS and LINQ code in the .NET projects you create with Visual Studio "Orcas." PDC 2005 has four WinFS breakout sessions. Here's the description of DAT312—"WinFS" and ADO.NET: Future Directions for Data Access Scenarios (Samuel Druker)—that contains references to ObjectSpaces and "integrated query functionality:"

The next generation of ADO.NET incorporates innovations that integrate Entities, Relationships, Associations, a seamless CLR object programming surface, and flexible storage mapping for programming to data at all tiers. These technologies address the needs for "WinFS" data modeling and programming scenarios on the desktop and server, as well as the requirements from the ObjectSpaces project. This session discusses how ADO.NET entities will form the core for data integration, enabling the interoperability of applications and modules by providing a high-level framework for programming with data that includes integrated query functionality.

Following are links to the other three WinFS-specific sessions—DAT200 Future Directions for Data-Driven Applications: Storage, Applications, API’s (David Campbell); DAT209 "WinFS" Future Directions: An Overview (Shishir Mehrotra); and DAT310 "WinFS" Future Directions: Building Data Centric Applications Using Windows Presentation Foundation ("Avalon") and Windows Forms (Ramesh Nagarajan). Robert Scoble's one-hour Channel 9 video with members of the WinFS team includes a demonstration of some WinFS features and applications. The demo starts at about 11:00:00 into the program. As to the ultimate release of WinFS, Paul Thurrott bases the following timeline on "internal Microsoft documentation:"

WinFS Beta 1 will be followed by at least one Community Technology Preview (CTP) release, which is currently due on February 15, 2006. Then, on May 1, 2006, Microsoft is scheduled to release WinFS Beta 2. Beta 3 is currently scheduled for November 15, 2006, with a Beta 3 Refresh release expected in April 2007. WinFS is currently scheduled for RTM in Q3 2007, well after Longhorn Server is released.

--rj Technorati: LINQ, COmega, ADO.NET vNext, WinFS