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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Misleading SSMS Connection
Read a cautionary tale on how I've deceived the SSMS, then promptly forgot about it and, in turn, ultimately confused myself.
Advent of Code 2022
This December I'm solving Advent of Code in two languages at once - SQL and KQL. Here's where I'm posting the code and how far I think I'll get.
Default event_file path for Extended Events
Create an Extended Events session with just a filename and the .xel file lands somewhere - but where? Here's what the default path is and how to change it.
T-SQL Tuesday #156 - Wrap Up
Fifteen SQL bloggers answered one question: what turns ordinary code into production code? Here's what they taught me.
Testing the code (T-SQL Tuesday #156)
I picked the T-SQL Tuesday topic and still struggled to answer it. The quality of production code I value most: it has tests.
Production Code (T-SQL Tuesday #156)
I'm hosting T-SQL Tuesday this November. The question: which secret ingredient turns ordinary code into production-grade code?
Scary Scalar Functions - Part Four: Your Environment
You've learned why Scalar UDFs are slow and how to remove them. The last question: where do you even start? Here's how I triage them across a whole environment.