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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KDA: Echoes of Deception - Case 3
20 stolen cars with swapped license plates - using KQL to trace VIN changes through traffic data and find the common storage location.
KDA: Echoes of Deception - Case 2
Digitown's citizens are being targeted by phishing calls. Using KQL, I analyze call patterns - duration, hidden caller IDs, and disconnect behavior - to unmask the phisher.
KDA: Echoes of Deception - Case 1
Digitown's utility bills doubled overnight. Using KQL and the EXPLAIN feature, I dig through billing data to find duplicate charges and negative consumption.
KDA: Echoes of Deception - Onboarding
A walkthrough of the Kusto Detective Agency UI and the onboarding challenge - finding which detective earned the most bounty money in 2022.
Kusto Detective Agency - Intro
I have a soft spot for Kusto. This series walks through the Kusto Detective Agency challenges - data mysteries you solve with KQL instead of a magnifying glass.
Deploy at Low Priority
A utility script for deploying schema changes without a maintenance window - using a time-based loop, lock checking, and GOTO to minimize blocking on busy SQL Servers.
Why is fn_xe_file_target_read_file the worst SQL function?
A rant about fn_xe_file_target_read_file - the nvarchar(max) return type, broken time filtering, and the circular dependency for finding rollover files.