Deep Dive
Scary Scalar Functions - Part One: Parallelism
Scalar UDFs silently force your query to run serially, killing parallelism. Even a reference through a view, computed column, or check constraint does it.
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
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.
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.
SQL Server Module Signing for Secure Cross-Database Access
I keep relearning how to set up secure cross-database access, so here's the reminder: a diagram plus a full follow-along example you can run yourself.