Deep Dive
Async stats update causing blocking
How lock partitioning causes async stats updates to block during online index rebuilds with WAIT_AT_LOW_PRIORITY - full repro and the SQL Server 2022 fix.
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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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.
IS Lock in RCSI Enabled Database
I found an IS lock in a deadlock report on an RCSI database. That shouldn't be possible. Here's what caused it.