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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KEEP PLAN Demystified
Ever wondered what the KEEP PLAN hint actually does? The docs are vague, so I tested it against every recompilation threshold to find out.
Extended Events Timezones
Open an XE event file in SSMS and the timestamps stare back at you. Local time or server time? I spun up a container in another timezone to find out.
The SQLBits 2022, or There and Back Again
My first in-person conference, my first time speaking, and a costume that needed a face mask. A SQLBits 2022 recap told in Lord of the Rings quotes.
SQL Wordle Series - Part Two: Playing
Last time we cheated. This time we actually play: a set-based scoring engine in TSQL, duplicate letters and all.
SQL Wordle Series - Part One: Cheating
Your Twitter feed is probably already full of Wordle posts, so why not one more? Let's start the series the lazy way: by cheating.
Expecting Subvertations
How can 15 be less than 13? A perfect storm of bad assumptions about sql_variant comparison rules.
How to audit data modifications with surgical precision
A colleague needed to find who was changing a specific cell in a busy table. SQL Audit was too noisy, Query Store too vague. I found a way to combine triggers with Extended Events for surgical precision.