Sunday, March 30, 2008

Links Of The Week 20080330

Who needs SQL links when you have this gem?

Check out (grand)ma in the background, she doesn't miss a beat.

Friday, March 28, 2008

How To Use COALESCE And NULLIF To Prevent Updating Columns When A Parameter IS NULL Or A Default Value

A variation of this question popped up twice in the SQL programming newsgroup since yesterday, this means it is time for a blogpost.
Let's say you have a proc like this




CREATE PROC prUpdateTable
@Salesman
int = -1
AS

..........

If the user calls the proc like this exec prUpdateTable null then @Salesman will be null, if the user calls the proc like this exec prUpdateTable then the value of @Salesman will be -1. In both of this cases you don't want to change the value of the column. What can you do?
You can use a combination of NULLIF and COALESCE to handle this. Your update statement would look like this




UPDATE table
SET
Column = COALESCE(NULLIF(@variable,-1),Column)



Here is some code to demonstrate that




CREATE TABLE #foo (id int,salesman int)
INSERT #foo VALUES(1,1)
INSERT #foo VALUES(2,1)
INSERT #foo VALUES(3,1)
INSERT #foo VALUES(4,1)



SELECT * FROM #foo
-------------
1 1
2 1
3 1
4 1

DECLARE @salesman int
SELECT
@salesman = 5

--Column value will change to 5
UPDATE #foo
SET salesman = COALESCE(NULLIF(@salesman,-1),salesman)
WHERE ID =1

--Column value won't change
SELECT @salesman = -1
UPDATE #foo
SET salesman = COALESCE(NULLIF(@salesman,-1),salesman)
WHERE ID =2

--Column value won't change
SELECT @salesman = NULL
UPDATE #foo
SET salesman = COALESCE(NULLIF(@salesman,-1),salesman)
WHERE ID =3

--Column value will change to 3
SELECT @salesman = 3
UPDATE #foo
SET salesman = COALESCE(NULLIF(@salesman,-1),salesman)
WHERE ID =4

--And here is the output, as you can see when @salesman was -1 or NULL the table did not get updated
SELECT * FROM #foo
-------------
1 5
2 1
3 1
4 3

DROP TABLE #foo





As you can see only the first and the last update statement changed the value of the salesman column
Of course you would never do this if you were to update only one column, you would skip the update instead. If you have to update multiple columns then this is something you can use instead of writing a bunch of dynamic SQL or nested IF statements.




Tuesday, March 25, 2008

Technet Radio: A Look Inside SQLCAT (SQL Customer Advisory Team)

Channel9 has a podcast with the SQLCAT team.

On this episode of TechNet Radio, We learn more about SQL CAT – the SQL Customer Advisory Team. With Launch of SQL 2008 on the way, the SQL CAT team has been working hard preparing lists of best practices, recommendations, technical whitepapers and technical end-to-end case studies on customer implementations.

Listen to it here: http://channel9.msdn.com/ShowPost.aspx?PostID=392382#392382

Saturday, March 22, 2008

Links Of The Week 20080322

Here are the links for this week

Database
Programming Policy-Based Management with SMO - Part 1 - Intro
Programming Policy-Based Management with SMO - Part 2 - Conditions
Programming Policy-Based Management with SMO - Part 3 - ExpressionNode and Policy
Programming Policy-Based Management with SMO - Part 4 - Introducing ObjectSets
Programming Policy-Based Management with SMO - Part 5 - TargetSets and TargetSetLevels
Programming Policy-Based Management with SMO - Part 6 - Categories, Subscriptions, Wrapup
How It Works: SQL Server 2005 I/O Affinity and NUMA Don't Always Mix
Database Programming: The String Concatenation XML Trick, Sans Entitization
Database Programming: The String Concatenation XML Trick, Finalized
SQL Server 2008: Interesting Full-Text Dynamic Management Function
Minimal Logging changes in SQL Server 2008 (part-1)
More about sparse columns and column_sets
Which to use: "<>" or "!="?
Hanselminutes #105 - Rocky Lhotka on Data Access Mania, LINQ and CSLA.NET
geekSpeak Recording: Extending SQL Server Integration Services with Reza Madani

Non DB tech
Unit Testing for Silverlight...
IronPython and the DLR march on
The Weekly Source Code 21 - ASP.NET MVC Preview 2 Source Code
Hanselminutes Podcast 104 - Dave Laribee on ALT.NET
The First Rule of Programming: It's Always Your Fault
The Weekly Source Code 20 - A Web Framework for Every Language
It’s common sense, stupid: How Not to Evangelize Unit Testing
Getting LINQ to SQL and LINQ to Entities to use NOLOCK
Google's Design Guidelines
Microsoft give an awesome response to the guy whose XBox was cleaned
Joe Duffy and Igor Ostrovsky: Parallel LINQ under the hood
FLOSS Weekly 27: Ward Cunningham

Non tech
TheGoogle.com - a Google offering for older adults
Open Letter to Comcast: STAY OUT OF MY COMPUTER!
The Laptop Cat [Pic]
Questions on Bear Stearns buyout - shareholders want answers on how the deal was arranged, and gained government approval and financing, all in a few hours, and seemingly without alternative bidders.

Thursday, March 20, 2008

SOT: I found a new 'worst query'

Before you ask, SOT means Slightly Off Topic :-())

Take a look at Hi, I need help on simplyfying this Update query!

I don't even want to count the nested SELECTS, The query is 688 lines long, somehow schadenfreude enters my mind.

Now where does the update come into the picture?

Monday, March 17, 2008

Links Of The Week 20080317

Here are the links for this week

Database
TechNet Radio: SQL 2008 Part 2 of 2: Management, Troubleshooting and Throttling
SQL Server: XQuery/XPath, Retrieval Functions
sp_send_dbmail in a transaction with @query causes unresolvable deadlock
New Features Announced In SQL Server 2008
SQL Down Under show 35 - Roger Doherty - SQL Server 2008 for Database Developers
Applying SQL Server Service Packs and HotFixes
Database Programming: The String Concatenation XML Trick Revisited (Or, Adam Is Right, But We Can Fix It)
Geek City: Nonclustered Index Keys
Sybase iAnywhere Unveils Advantage Database Server 9.0
SQL Server Integration Services and Clustering - confguration gotcha to ensure SSIS works with failover of cluster!

Non DB tech
How the BBC rendered a spinning globe in 1985
I wrote Super Pac-Man: More confessions of an ex-Atari employee
From BFS to ZFS: past, present, and future of file systems
LINQPad.net - So Great! So Great!
.NET Rocks! #324 - Emre Kiciman on AjaxView
Mashups with SyndicationFeed and LINQ
Microsoft Research Offers Behind-the-Scenes Look at Future of Computing
IBM Researchers Develop World’s Tiniest Nanophotonic Switch to route optical data between cores in future computer chips
Getting up to speed with ASP.NET and the 3.5 Extensions
Using Unity and the ASP.NET MVC Preview 2
PowerShell Plus is now official!
List Of .NET Dependency Injection Containers (IOC).
The Weekly Source Code 19 - LINQ and More What, Less How
You Know, There's a Much Easier Way...

Non tech
Man had $12,000 in debts, repaid $15,000 over 8 yrs, still owes $12,200. Credit card industry stopped him from testifying to congressional panel
XKCD on mythbusters...
JP Morgan "buys" Bear Stearns for $2 a share, Fed flips the actual bill
2008-03-11, Jim Cramer: "No! No! No! Bear Stearns is not in trouble. If anything, they’re more likely to be taken over. Don’t move your money from Bear."
English is our language [PIC]

Wednesday, March 12, 2008

6th Annual Financial Services Developer Conference

I went to the 6th Annual Financial Services Developer Conference today in New York City. This year’s focus was on High Performance Computing (HPC). I must say that I have enjoyed this conference a lot. It seems that SQL Server is very prevalent on the street. The OLAP capabilities of SQL Server are making Sybase slowly disappear from Wall Street. Financial firms are doing some very interesting stuff; there is a hedge fund which records an earnings call, runs it through some voice stress analysis software and based on the outcome of that will short or long the stock. You should hear the stories of how financial firms handle IT, the innovation is happening in the financial markets. I also saw a couple of very cool WPF applications. Check out the demos from Lab49: http://www.lab49.com/insidethelab/demos
Visit http://www.financialdevelopers.com/ to download The Silverlight 2 Retail Financial Services Demonstrator

Financial Services Developer Conference

Carl Franklin from Dotnetrocks recorded a podcast at the event, this podcast was about concurrency and how to handle multi-core programming. You should definitely check it out when it becomes available on dotnetrocks. If you are interested about PLINQ and concurrent programming with .NET then visit this site: http://msdn2.microsoft.com/en-us/concurrency/default.aspx

Dotnetrocks Podcast Recording

Tomorrow there are three sessions at the same time that I want to attend
Software Engineering with VSTS
Parallelize you .Net applications with parallel extensions to the .NET framework.
Useful evolution: Programming the New features in SQL Server 2008.

I have my blackcrackberry with me so if you are attending the event tomorrow then send me an email at FirstName.LastName@dowjones.com and maybe we can discuss about this event during lunch.

Sunday, March 09, 2008

Links Of The Week 20080309

Here are the links for this week

Database
Podcast: SQL Down Under show 34 - Geoff Hiten - SQL Server Clustering and SANs
Feature synergy in SQL Server 2008
How It Works: SQLIOSim - Checksums
Change collation in tempdb
Query Optimization DMV du jour - sys.dm_exec_query_optimizer_info
Data Warehouse Scalability Features in SQL Server 2008
SQL Server 2008: Changes to enabling FILESTREAM from CTP-6 onwards
Appending Data Using SQL 2008 Filestream
SSDS is Microsoft's Amazon S3 competitor
Manageability Presentation from the SQL2K8 Launch

Non DB tech
Sun: We'll put Java on the iPhone (InfoWorld)
Filters for Google Reader
Hanselminutes Podcast 103 - Quetzal Bradley on Testing after Unit Tests and the Myth of Code Coverage
ASP.NET MVC Session at Mix08, TDD and MvcMockHelpers
Steve Souders asks: "How green is your web page?"
A Question of Programming Ethics
Why I Love Hackers
The Weekly Source Code 18 - Deep Zoom (Seadragon) Silverlight 2 MultiScaleImage Mouse Wheel Zooming and Panning Edition
Google Releases an API for Contacts

Mix08 Sessions
Adding Instant Messaging to Any Site
Keiji Kanazawa, Nikhil Kothari
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T03.wmv

Advanced Cross-Browser Layout with Internet Explorer 8
Scott Dickens
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/CT07.wmv

Advanced Search Engine Optimization: Generating More Site Traffic from Search
Nathan Buggia
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BT03.wmv

Bringing Hosters and Developers Together with IIS7
Robert Cameron, Tito Leverette
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BT08.wmv

Building AOL's High Performance, Enterprise Wide Mail Application With Silverlight 2
Eric Hoffman, Marc Katchay, Stefan Gal
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BT01.wmv

Building Applications and Services with .NET Framework 3.5
Justin Smith
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T26.wmv

Building Great AJAX Applications from Scratch Using ASP.NET 3.5 and Visual Studio 2008
Brad Adams
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T34.wmv

Building Rich Internet Applications Using Microsoft Silverlight 2, Part 1
Joe Stegman, Mike Harsh
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/CT01.wmv

Building Rich Internet Applications Using Microsoft Silverlight 2, Part 2
Joe Stegman, Mike Harsh
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/CT02.wmv

Creating a RESTful API with Windows Communication Foundation
Haider Sabri, Paul Walker, Viphak Lay
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T01.wmv

Creating Better User Experiences: Design Methods
Dan Harrelson, Kim Lenox
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/UX07.wmv

Creating Better User Experiences: Design Strategy
Dan Harrelson, Kim Lenox
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/UX04.wmv

Creating Better User Experiences: Information Architecture
Dan Harrelson, Kim Lenox
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/UX06.wmv

Creating Better User Experiences: Interaction Design
Dan Harrelson, Kim Lenox
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/UX05.wmv

Creating Rich, Dynamic User Interfaces with Silverlight 2
Karen Corby
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T20.wmv

Design at Speed of Light
Cinthya Urasaki, Daniel Makoski, John Reid, Tim Wood, Zachary Jean Paradis
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL02.wmv

Developing Applications with Microsoft Virtual Earth
Chris Pendleton
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T17.wmv

Developing Applications Using the Model View Controller Pattern
Scott Hanselman
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T22.wmv

Developing Data Driven Applications Using ASP.NET Dynamic Data Controls
David Ebbo
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T24.wmv

Developing with Windows Live
Angus Logan
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T29.wmv

E-commerce Done Right
Gerard Johnson, Matthews Rechs, Nicholas Rockwell, Steve Nelson
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL12.wmv

Encoding Video for Microsoft Silverlight
Ben Waggoner
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BCT07.wmv

Everything You Need to Know about Diagnostics and Debugging on Microsoft Internet Information Services 7
Mai-lan Tomsen Bukovec
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T06.wmv

Exploring Moonlight: Novell's Implementation of Silverlight on Linux
Miguel de Icaza
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T31.wmv

From Flash to Silverlight: A Rosetta Stone
Rick Barazza
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T30.wmv

From Long Tail to Fuzzy Tale: Why "Fuzzy" Is the New Clear
David Armano
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/UX02.wmv

Getting Clued In to Experience Management
Lou Carbone
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/UX01.wmv

How Design Impacts the Bottom Line
Dave Blakely, David Watson, Jason Brush, Jimmy Kim, Luke Wroblewski, Will Tschumy
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL11.wmv

I Wanna Go Mobile!
Chad Stoller, David-Michael Davies, Derrick Oien, Eric Breitbard, George Linardos, Michael Platt
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL09.wmv

Integrating Media in Silverlight Applications
Ed Maia
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BCT05.wmv

Integrating Your Site With Internet Explorer 8
Jane Kim
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T21.wmv

Internationalizing XAML Applications in Windows Presentation Foundation and Microsoft Silverlight
Ken Azuma, Laurence Moroney, Ted Kitamura
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T15.wmv

Introducing SQL Server Data Services
Nigel Ellis
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BT05.wmv

Is Web 2.0 Sustainable? What business models will work?
Dave McClure, Don Dodge, Kimbal Musck, Robert Scoble, Ryan McIntyre
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL15.wmv

Keynote I
Dean Hachamovitch, Ray Ozzie, Scott Guthrie
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/KYN0801.wmv

Keynote II
Guy Kawasaki, Steve Ballmer
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/KYN0802.wmv

Making it Simple: Designer/Developer Workflow
Christian Schormann, Ken Azuma, Marcelo Marer, Mark Ligameri, Robby Ingebretsen, Robert Tuttle, Ryan Lane
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL01.wmv

Microsoft Expression Web: From Comp, to CSS, to Code!
Nishant Kothary, Tyler Simpson
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/C04.wmv

Mobile Devices and Microsoft Silverlight: A Primer on the New Technology
Amit Chopra, David Kline
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T12.wmv

Monetization 101
Erynn Petersen
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BT07.wmv

Opportunities and Challenges in Mashing Up the Web
Aaron Fulkerson, Andi Gutmans, Michael Scherotter, Sam Ramji, Shawn Burke
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL13.wmv

Overview of Microsoft Ad Formats
Alam Ali
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/C05.wmv

Partying with PHP on Microsoft Internet Information Services 7
Drew Robbins
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T27.wmv

Real World Design: Working with Silverlight and WPF in the Design Studio
Beau Ambur, Chip Aubry, Chris Bernard, Nathan Dunlap, Rich Weston
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL16.wmv

Real-World AJAX with ASP.NET
Nikhil Kothari
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T16.wmv

RESTful Data Services with the ADO.NET Data Services Framework
Pablo Castro
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T07.wmv

Silverlight and Advertising
Eric Schmidt
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BT06.wmv

Silverlight as a Gaming Platform
Joel Neubeck, Scott McAndrew
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/CT03.wmv

Social Networks: Where Are They Taking Us?
David Morin, Garrett Camp, Guy Kawasaki, John Richards, Joseph Smarr, Marc Canter
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL08.wmv

The Back of the Napkin: Solving Design Problems (and Selling Your Solutions) with Pictures
Dan Roam
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/UX03.wmv

The Business of Microsoft Silverlight
Danny Riddell
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/B01.wmv

The Human Brain Relationship: Advanced and Adaptive User Interfaces
Ya'akov Greenshpan, Yochay Kiriaty
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/CT04.wmv

The Open Question
Andi Gutmans, Miguel de Icaza, Mike Schroepfer, Sam Ramji
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL04.wmv

Tools and Applications for Publishers
Rishi Bal
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T18.wmv

Touch Me: Where Are Interfaces Going?
Chris Bernard, Dale Herigstad, Daniel Makoski, Dave Wolfe, Doug Cook, Yoshihiro Saito
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL10.wmv

Understanding Microsoft Partner Programs for Designers, Developers, and Agencies
Bill Vlandis, Hakan Soderbom
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BCT03.wmv

Using Microsoft Silverlight for Creating Rich Mobile User Experiences
Giorgio Sardo
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/C02.wmv

Virgins, Spaceships and Hob-nailed Boots!
Paul Dawson
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/C03.wmv

Web 2.0 and Beyond: What Is the Business Reality?
Bryan Biniak, Chris Saad, Frank Arrigo, Loic Le Meur, Tim Kendall
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL05.wmv

Welcome to Internet Explorer 8
Chris Wilson
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/BCT08.wmv

What Is the face of the next Web?
Anthony Franco, Chris Bernard, Garrick Schmitt, Mark Kurtz, Paul Dain, Tjeerd Hoek
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL07.wmv

What's New in Windows Presentation Foundation 3.5
Rob Relyea
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T11.wmv

What's the Secret Formula?
Dan Harrelson, Daniel Makoski, Jensen Harris, Mike Schroepfer, Nishant Kothary
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/PNL14.wmv

Windows Presentation Foundation Using Microsoft Visual Studio 2008
Mark Wilson-Thomas
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T02.wmv

Working with Data and Web Services in Microsoft Silverlight 2
Eugene Osovetsky
http://msstudios.vo.llnwd.net/o21/mix08/08_WMVs/T13.wmv



Non tech
Battle Plans [Pic]
History: From Moses to Hitler, Mike Tyson and Bill Clinton ( amazing pic )
Olympics clean up Chinese style: Inside Beijing's shocking death camp for cats [PICS]
Apple, Google... And then, You. [Pic]
Geek Flow Chart [Pic]
Fruits. Water. Action! (pics)

StrataFrame Or CSLA.NET, Which Framework Would You Use?

If you would have to choose between StrataFrame or CSLA.NET, which one would you pick?
The team I am part of at work is trying to pick a framework for new development and they like these two the best. Are these two something you would pick or do you know a better one?

CSLA.NET: http://www.lhotka.net/cslanet/
StrataFrame: http://www.strataframe.net/

Also keep in mind that while CSLA.NET is free, StrataFrame is not.

Friday, March 07, 2008

Video: SQL Server Data Services and the Future of Data in the Cloud

Channel 9 has a 45 minute video with Dave Campbell about SQL Server Data Services. maybe this video will answer some of the question you might have about SQL Server Data Services



Watch it here: http://channel9.msdn.com/ShowPost.aspx?PostID=388698#388698

Wednesday, March 05, 2008

Microsoft Announces SQL Server Data Services

What is Microsoft SQL Server Data Services?
SQL Server Data Service (SSDS) is a highly scalable and cost-effective on-demand data storage and query processing web service. It is built on robust SQL Server technologies and helps guarantees a business-ready service level agreement covering high availability, performance and security features. Microsoft SSDS is accessible using standards based protocols (SOAP, REST) for quick provisioning of on-demand data-driven & mashup applications.

How does Microsoft SQL Server Data Services differ from traditional on premise relational SQL Server Database?
SQL Server Data Services is a storage and query processing utility providing mega scale, high availability, reliability, and geo-distributed data services in the Cloud. Customers use the service on-demand, with no up-front cost. It eliminates the initial investment in hardware and software and the on-going cost for storage administration, scale maintenance. Developers and Service providers can quickly run their on-demand applications with minimal infrastructure cost.

What can I do with SQL Server Data Services?
Customers can use SQL Server Data Services to store virtually any amount of data in the Cloud. They can query and modify data as required by the specific business scenarios. SQL Server Data Services support standards-based REST and SOAP interfaces designed to work with any Internet-development toolkit. The primary wire format is XML. Developers and service providers can quickly run on-demand applications with ease. The data has flexible schema which can be modified dynamically by the application. The data is provided with high availability and reliability virtually anywhere, anytime.

Rest of the FAQs here: http://www.microsoft.com/sql/dataservices/faq.mspx
Main SQL Server Data Services site here: http://www.microsoft.com/sql/dataservices/default.mspx