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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Latest posts
KDA: Echoes of Deception - Case 7
A fugitive cyber-criminal, a wingsuit, and 24 million flight records. Somewhere between Doha and Dublin, Krypto jumped between planes mid-air.
KDA: Echoes of Deception - Case 6
A cryptic message, a book cipher hidden in art provenance records, and a trail of clues leading to the leader of a shadowy cyber organization.
Red Flags in Your Query (T-SQL Tuesday #200)
When I'm looking at a query, I bet it's bad if I see... a shopping list of red flags I've learned to spot, from AI-generated code to SSMS map mode gut checks.
KDA: Echoes of Deception - Case 5
A deleted podcast episode, 17 million archive log entries, and KQL's time series analysis to find the backup that was never supposed to survive.
KDA: Echoes of Deception - Case 4
Someone hacked Digitown's municipality and stole classified documents. 45 million rows of router traffic, an IP lookup table, and KQL's anomaly detection to find who did it.
My Toolbox - AI
I trusted AI to redesign this blog, be my personal assistant, and organize my life. But I won't let it near a production database. Here's why that's not a contradiction - and what I learned about trust along the way.
Inspecting TSQL Abstract Syntax Trees
What does SQL Server actually see when it parses your code? I built a free web tool that lets you paste TSQL and explore the abstract syntax tree - click a token, see the node, read the fragment.