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The PASS Performance Virtual Chapter has a tradition of yearly “Palooza events”, in which there are a few back-to-back online performance sessions by great speakers from all around the world. I have the honor to speak in this year’s Performance Palooza, which will take place this Thursday, July 23. I will speak about Columnstore, a technology that fascinates me and is a true game changer. The session is called Columnstore Indexes – Questions and Answers (click here to registe

Thanks to everyone who attended my 24 Hours of PASS session, The Data Loading Performance Presentation. It was a lot of fun taking part in such a special event. The slide deck and scripts I used in the session can be downloaded here. #sessions #performance #community #PASS

Next week, I’m going to visit London and Copenhagen for SQLBits and SQLRally Nordic. It’s going to be intense and fun. SQLRally On Wednesday, March 4, at 4:45PM, I’ll deliver my session “Query Progress Tracking in SQL Server” at SQLRally in Copenhagen. The session talks about a big pain in our job: How can we know when a certain process will finish its execution? It covers the ways SQL Server allows us to track the progress of processes and queries, and exposes some fun inter

New versions have bombastic and catchy features. But a lot of times, the little, hidden features are the ones that matter the most. I already wrote in the past about the small changes that make a difference in SQL Server 2012, and yesterday about the maturity of SQL Server 2014. Here’s another classic example for a feature nobody talked about that can make a huge difference. sys.dm_exec_query_profiles is a new DMV in SQL Server 2014. According to the documentation, this DMV:

Views, table variables and local variables are great in terms of programming principles. But In terms of performance, they can be a honey trap: They don’t scream “DANGER!” like cursors or user defined functions, but they can cause serious problems very easily. That’s why I call them “The Axis Of Evil”. I know – maybe it’s a little extreme, but let me explain. Why Views Are Evil The truth is they are not. It’s the way people sometimes use them that is evil. Views are great for

I read this awesome post by Joe Sack, titled “Detecting Cardinality Estimate Issues with sys.dm_exec_query_stats”. I was amazed by the beauty of his detection query, ran it on my environment, and discovered some interesting things. Then I revised it a little to reveal more information and filter out more irrelevant data. You can find the revised query below. For queries where the difference between the estimated and actual rows is greater than 30,000, It returns the batch tex