How to
Query Hash and Query Plan Hash Mapping
DMVs and Query Store store the query hash as binary(8), but Extended Events shows a number, and the two refuse to match. Here's how to map between them.
Notes from a TSQL trench
Database stuff,
with a side of memes.
Long-form notes on TSQL performance, Extended Events, Query Store and the tooling around them. Written from the trenches, not the slide deck.
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My Toolbox - Everything
Another productivity tool in my toolbox that I use daily. This time it's about file search. Everything will help you find... well, everything.
Unexpected Blocking during the Indexed View Creation
Here are the chronicles of my struggles to add a large Clustered index to a View without causing an outage.
My Toolbox - Greenshot
Print Screen and Paint never cut it for me. Greenshot did: precise region capture, a real annotation editor, obfuscation, and one-key sharing. Here's the tour.
Scary Scalar Functions - Part Three: The Cure
Nuke them from orbit, or inline them. The practical ways to neutralize Scalar UDF performance pain, from a free SCHEMABINDING win to a full ITVF rewrite.
What's in a name? (T-SQL Tuesday #152)
My T-SQL Tuesday rant: an app that connects as '.Net SqlClient Data Provider' turns debugging into a manhunt. Please, name your apps.
Scary Scalar Functions - Part Two: Performance
A Scalar function that does literally nothing still runs over 20 times slower. Here is the proof, measured four different ways.
What is causing my constraint to be untrusted?
You fix an untrusted constraint, and by morning it's back to untrusted. Here's how to catch the process responsible, using Extended Events.