Query-Performance

Category: query-performance

My Performance Tuning Precon and Git Session at PASS Data Community Summit 2023

My Performance Tuning Precon and Git Session at PASS Data Community Summit 2023

I’m thrilled to be heading to Seattle in November for the PASS Data Community Summit. My favorite things about the PASS Summit are making connections, learning from folks, broading my horizons, helping build a vibrant community, and teaching.

Teaching is a great privilege, and I’m excited to be giving both a pre-conference session and a regular session. I chat about the sessions in this ~4 minute video.

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Learner's Guide to SQL Server Query Tuning

Learner's Guide to SQL Server Query Tuning

Following on from my Learner’s Guide to SQL Server Performance Triage, I’m tackling Query Tuning. In this guide, I’m experimenting with an outline style rather than expanding each paragraph.

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How to Cause a Simple Spill to tempdb

How to Cause a Simple Spill to tempdb

Sometimes it’s useful to know how to cause a problem.

Maybe you’ve never encountered the problem, and want to get hands-on experience. Maybe you’re testing a monitoring tool, and want to see if a condition flags an alert. Maybe you’re testing out a new client tool, and want to see how it displays it.

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Take the SQLChallenge: Tuning a Stored Procedure

Take the SQLChallenge: Tuning a Stored Procedure

I’ve just published a new SQLChallenge course, and I think it’s one of the best ones yet.

Your mission is to:

  1. Identify which statement is slowing down our stored procedure the most
  2. Tune the code to speed it up. You can change the query that is slow as well as anything else in the procedure that will help you make that statement faster.

In the solution videos, I’ll step through multiple strategies to figure out which statement in the procedure is slowing it down the most – because in real life, you need to have a whole bag of tricks in different situations. 

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Find the Scalar Function Call: What It Means When It Hides in Probe Residual

Find the Scalar Function Call: What It Means When It Hides in Probe Residual

User defined functions are fairly simple to create in SQL Server, but figuring out exactly how they are being used can take a little time - even in a simple execution plan. This is because the functions can be tucked away into lots of different operators in the plan, even join operators.

The good news: once you learn what to look for, it’s not terribly complicated. There are some fancy terms involved, but the definitions are pretty simple.

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Fake News about Auto Parameterization/Simple Parameterization

Fake News about Auto Parameterization/Simple Parameterization

I saw a question on Twitter today that took me down a little rabbit hole. And when I go down rabbit holes, I like to blog about it! There’s a TLDR at the bottom of this post if you’re short on time.

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