Helping to make Hadoop easier by going Metro!

We are proud to announce that the community technology preview (CTP) of ApacheTM HadoopTM-based Services for Windows Azure (or Hadoop on Azure) is now available. As noted in on the SQL Server Data Platform Insider blog, the CTP is by invite only While Hadoop is important to our customers for performance, scalability, and extreme… Read more

A Computed Column Defined with a User-Defined Function Might Impact Query Performance

Author: Kun Cheng Reviewers: Shaun Tinline-Jones, Silvano Coriani, Steve Howard, Thomas Kejser, Sanjay Mishra A computed column is computed from an expression that can use other columns in the same table. The expression can be a noncomputed column name, constant, function, and any combination of these connected by one or more operators, but the expression… Read more

Writing New Hash Functions for SQL Server

Author: Thomas Kejser Contributors/Reviewers: Alexei Khalyako, Jerome Halmans, Fabricio Voznika, Sedat Yogurtcuoglu, Mike Ruthruff, Tobias Ternstrom and Steve Howard In this blog, I will explore ideas for extending SQL Server with new, fast hash functions. As will be shown, the high speed, built in functions CHECKSUM and BINARY_CHECKSUM are not always optimal hash functions, when… Read more

What’s so BIG about “Big Data”?

As announced during the PASS Summit 2011 Day One Keynote, we are diving deeper into the world of Big Data by embracing and contributing to the open source community and Hadoop. We’ve had a lot of good coverage on this topic with some examples below. Microsoft Expands Data Platform With SQL Server 2012, New Investments… Read more

Successfully execute an INSERT, UPDATE and DELETE against a Database Snapshot

Author: Shaun Tinline-Jones Reviewers: Mike Ruthruff, Sanjay Mishra, Alexei Khalyako Not too long ago an ISV that developed solutions using SQL Server as the RDBMS, asked me how they could query a database as at a point in time. This was a relatively easy answer, thanks to the Database Snapshot feature. I was however surprised at the… Read more


The SQLPASS 2011 summit is upon us again and all of our flocking to our fair city Seattle for our yearly technical-and-karoke fest!  If you are up for some technical deep dives, here is the list PASS sessions presented by SQLCAT!    And don’t forget to check out the Birds of Feather event – the tech… Read more

Maximizing SQL Server Throughput with RSS Tuning

Author: Kun Cheng Reviewers: Thomas Kejser, Curt Peterson, James Podgorski, Christian Martinez, Mike Ruthruff Receive-Side Scaling (RSS) was introduced in Windows 2003 to improve Windows scalability to handle heavy network traffic, which is typically the case for SQL Server OLTP workload. For more details about RSS improvement on Windows 2008, please check out the whitepaper –… Read more

“QUOTED_IDENTIFIER” causes Unexpected Query Plan for Persisted Computed Column query

Author: Shaun Tinline-Jones Technical Reviewers: Thomas Kejser, Steve Howard, Jaime Alva Bravo, Kun Cheng, Jimmy May Note: Validation for this post was performed in the SQL CAT Customer Lab on an HP Proliant DL580 G7, Intel Xeon Nehalem E7-4870 2.40 GHz 4 socket, 10 physical cores, 20 logical cores for a total of 40 physical… Read more

SSAS Maestros August 2011 Update

As noted in our blog post Announcing SSAS Maestros v1.2, we had a great Analysis Services Level 500 deep dive sessions in Redmond and Madrid back in June/July 2011.  Saying this, we do have some quick updates on the SSAS Maestros current status:   Annoucing the first set of SSAS Maestros: We have completed the… Read more

Unintended Consequences of Scalar-Valued User Defined Functions

Author:            Chuck Heinzelman Reviewers:     Kevin Cox, Dan Jones, Lara Rubbelke   During a customer engagement, we noticed a query that was taking a long time to execute.  We saw that the query had a scalar-valued User Defined Function (UDF) encapsulating functionality in the SELECT clause.  To understand why this could be a problem, you need… Read more