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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SQL SERVER – Reading Transaction Log to Identified Who Dropped a Table

The other day I received a distress email from a user who wanted to find out who has dropped a table or column from their database. During the On Demand (55 minutes) consultation, not only I was able to help them with restoring their lost data but also was able to find out which user had actually dropped their table “accidentally”. We were lucky enough that the user had a database in full recovery model, hence their transaction log recorded every detail needed.

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