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Tag : locking

Paul White : Improving the Row Numbering Median Solution

Paul White (@SQL_Kiwi) takes one more look at medians, this time describing how a locking hint can help improve the performance of a pre-2012 solution.

Paul White : Locking and Performance

Paul White (@SQL_Kiwi) follows up a great post on calculating medians with some information on how locking can affect query performance, often undetected.

High LCK_M_SCH_M waits

Aaron Bertrand (@AaronBertrand) describes a scenario where Common Criteria compliance was deemed the cause of high LCK_M_SCH_M waits for multiple customers.

Bad habits : Putting NOLOCK everywhere

Aaron Bertrand (@AaronBertrand) discusses the NOLOCK hint in SQL Server, and why you want to avoid slapping it onto every table mentioned in every query.