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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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.
Why my way of writing SQL is superior
Semicolons, leading commas, single-letter aliases. Here is the SQL style everyone loves to argue about, and the practical reasons I refuse to budge.
Query Hash and Query Plan Hash Mapping
Ever struggled to match the binary hash from DMVs and Query Store against the numeric one in Extended Events? Let's fix that for good.
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.