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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Latest posts
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.
Don't Be Lazy
Sometimes the fastest help is the kind you find yourself. A rundown of the lazy question patterns I keep seeing in SQL help channels.
Short Code Examples (T-SQL Tuesday #143)
This month's T-SQL Tuesday invitation is from John McCormack. I'm sharing a few handy snippets I use on a regular basis - a time loop, impersonation testing, database recreation, and some RegEx for SSMS Find & Replace.
Discover potential obstacles in your design
One query against sys.messages can reveal every edge case SQL Server knows about before you commit to a new design.
Query Store default settings
Query Store comes with default settings - but are they what the documentation says? Let's find out using a simple Extended Events session.
Investigating Errors With Extended Events
Production errors are hard to reproduce. Here's my go-to Extended Events session that captures errors with their full TSQL calling stack.
Out with the old…
WordPress was making me hate blogging. Moving to Hugo, GitHub, and Azure Static Web Apps fixed that.