Parameter Sensitive Plan (PSP) optimization, new in SQL Server 2022 (compatibility level 160+)as part of Intelligent Query Processing. It’s Microsoft’s built-in fix for exactly the scenario you built: ParentId in Posts is wildly skewed (a handful of parent posts have…
All the functions. ASCII Animated Execution Plan: ASCII CHAR Animated Execution Plan: CHAR CHARINDEX Animated Execution Plan: CHARINDEX CONCAT Animated Execution Plan: CONCAT CONCAT_WS Animated Execution Plan: CONCAT_WS DIFFERENCE Animated Execution Plan: DIFFERENCE FORMATMESSAGE Animated Execution Plan: FORMATMESSAGE LEFT Animated…
Table variables versus #temp tables: Are you sure of that last one Mr. DBA? Checking the Properties the Estimates and Actuals are the same and even in Batch Mode. Ah.. Ronald you cheat because of the index.. nope I don’t.…
This week I worked an IoT table with partitioning to make data movement simpel and without locking.But what about the other way around… you have a huge table and want to make it partitioned, how can you do that? Well…
In the past you always tried to make queries faster by starting joining with the smallest table and end with the largest one, or visa versa, whatever you did.. you never got it very fast.. now lets take a closer…
I must admit, I have done it very often, encapsulate business logic in a function and use it in a select as this example of Erik Darling shows (this is from his Plan Cache Liars series, using sp_BlitzCache). As a…
Erik Darling has created a plugin/skill to analyze execution plans. (see: erikdarlingdata/claude-plugins: Claude Code plugins from Erik Darling Data ) well, lets use it in a convenient way by using the QueryStore and create an Actual plan and feed that…
My friend Erik Darling posted a video on Youtube ( (3) New Claude Plugin For SQL Server Query Plan Analysis – YouTube ) where he showed how to work with a Skill to analyze queryplan. “Two commands to install:/plugin marketplace…
The tenth and final part of my series on Craig Freedman’s SQL Server query-processing blog (part 9, 2008, is here). Craig’s posting slowed down in 2009 — seven more articles followed, heavy on I/O performance and hint pitfalls, before the…
Part 9 of my series on Craig Freedman’s SQL Server query-processing blog (part 8, 2007, is here). In 2008 Craig published 16 articles: deeper update internals, the ranking functions, a three-part warning about conversions, the reworked partitioning in SQL Server…
