SQL SERVER – Adding Values WITH OVER and PARTITION BY

Once in a while, I get questions where users have indeed explained the question well enough that I can easily understand their question. If I understand question quickly, I am always able to answer it efficiently as well. In this blog post, we will see one such question which I answered with keywords WITH OVER and PARTITION BY.

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SQL SERVER – How to Know Transaction Isolation Level for Each Session?

During recent, Comprehensive Database Performance Health Check, I had a very interesting scenario. I was hired by a customer to identify their system’s unexpected performance bottlenecks. I do these for a living so I am usually pretty comfortable. However, this customer was so unique that after their permission I am sharing you their story of transaction isolation level.

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SQL SERVER – Parallel Redo on AlwaysOn Secondary – DIRTY_PAGE_TABLE_LOCK

As most of you might know that my expert area in SQL Server in performance tuning. But, I also deal with almost every issue related to SQL Server engine. Many times, it so happens then clients call me for performance tuning and while fixing, we see some other problem. In this blog, we would learn about Parallel Redo on AlwaysOn Secondary causing new waits which were introduced in SQL Server 2016.

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