WinFS reborn: SQL Server as a file system

Fascinating interview with Quentin Clark, who led the cancelled WinFS project at Microsoft. Jon Udell is the interviewer.

Clark talks about how technology from WinFS is now emerging as the Entity Framework in ADO.NET (part of .NET 3.5 SP1) and the FileStream column type in SQL Server 2008 – a connection I’d already made at the Barcelona TechEd last year. He also mentions the new HierarchyID column type that enables fast querying of paths, the concept of rows which contain other rows. He adds that a future version of SQL Server will support the Win32 API so that it can support a file system:

In the next release we anticipate putting those two things together, the filesystem piece and the hierarchical ID piece, into a supported namespace. So you’ll be able to type //machinename/sharename, up pops an Explorer window, drag and drop a file into it, go back to the database, type SELECT *, and suddenly a record appears.

Put that together with the work Microsoft is doing on synchronization, and you get offline capability too – something more robust than offline files in Vista. Clark says SharePoint will also benefit from SQL Server’s file system features.

Note that Live Mesh does some of this too. I guess SQL Server is there in the Live Mesh back end, but it strikes me Microsoft is at risk of developing too many ways to do the same thing.

The piece of WinFS that shows no sign of returning is the shared data platform, which was meant to enable applications to share data:

… all that stuff is gone. The schemas, and a layer that we internally referred to as base, which was about the enforcement of the schemas, all that stuff we’ve put on the shelf. Because we didn’t need it.