Deep Dive
KEEP PLAN Demystified
The KEEP PLAN hint is supposed to relax recompilation thresholds, but the docs are vague. I test it against permanent and temp table statistics thresholds.
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
What's in a name? (T-SQL Tuesday #152)
My T-SQL Tuesday rant: an app that connects as '.Net SqlClient Data Provider' turns debugging into a manhunt. Please, name your apps.
Scary Scalar Functions - Part Two: Performance
A Scalar function that does literally nothing still runs over 20 times slower. Here is the proof, measured four different ways.
What is causing my constraint to be untrusted?
You fix an untrusted constraint, and by morning it's back to untrusted. Here's how to catch the process responsible, using Extended Events.
Scary Scalar Functions - Part One: Parallelism
Consultants hate me for this one weird trick. Because I'll be uncovering all the mess Scalar functions can cause in a series of articles.
Coding Standards (T-SQL Tuesday #151)
My T-SQL Tuesday #151 entry: the SQL habits I swear by, and the ones I'd ban from every codebase if I could.
New Extended Events in SQL Server 2022
SQL Server 2022's CTP has dropped. I diffed its Extended Events against 2019 and pulled out the few new ones worth a look.
Efficient Cheating at Lego Video Games
My daughter's LEGO game makes you re-enter every cheat on a clunky six-dial lock. So I built a TSQL solver to find the shortest path through all of them.