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Category: Query Store

Tracing Trigger Executions in SQL Server

Published 2026-01-06 by Kevin Feasel

Kendra Little does some investigating:

Triggers can be tricky to observe in SQL Server. When you need to understand exactly what a trigger is doing and what it impacts, Query Store and Extended Events both have something to offer, but using them effectively requires navigating some confusing nuances. Query Store tracks query-level executions aggregated by query_id, but has a habit of generating a lot of query_ids with different context settings for triggers. Extended Events can capture trigger module starts and individual statement completions within triggers.

This post walks through setting up both observation methods on a test trigger, then compares what each one shows. You’ll see how Query Store data gets spread across multiple query_ids and context_settings_id values, a variety of ways to trace triggers in XEvents, and why the numbers don’t always match up exactly between traces and Query Store.

This is definitely worth the read. Kendra does a great job laying things out in a thoughtful manner and provides a lot of additional insight.

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ABORT_QUERY_EXECUTION in SQL Server 2025

Published 2025-08-11 by Kevin Feasel

Joey D’Antoni pulls out the big guns:

However, SQL Server 2025 gives us a bigger hammer (DBAs love hammers). Building on top of the query store hints feature that was added in SQL Server 2022, ABORT_QUERY_EXECUTION simply blocks the exection of known problematic queries.

Read on to see how this works. Note that it will prevent the query from running at all, ever. As a result, if your main concern is “Hey, don’t run this during the busiest hours of the data for this database,” this particular hint is overkill.

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Query Store Plan Forcing and RECOMPILE

Published 2025-07-18 by Kevin Feasel

Vlad Drumea tests Betteridge’s Law of Headlines:

It’s 3AM and I’m curious if Query Store plan forcing works on queries that use the RECOMPILE hint (aka OPTION(RECOMPILE) ).
So might as well make a blog post out of it.

Hmm, on the one hand, Vlad blatantly violates Betteridge’s Law of Headlines, which loses points. On the other hand, Vlad dunks hard on LLMs, gaining points. I’m so conflicted right now…

But not about reading Vlad’s post. Go read it.

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Adaptive Joins and Equivalent Plans

Published 2025-07-15 by Kevin Feasel

Forrest McDaniel has a public service announcement:

In case you haven’t heard, moral decline is everywhere. The latest generation of query operators is a prime example of this rot. “But this is programming” you say, “what do morals have to do with anything?” No. This is SQL. And for us, we have the term morally equivalent plans which allows me to finally have an ethical excuse for sprinkling a post with degenerate puns.

I bit my tongue specifically to avoid doing exactly what Forrest does. So click through to read all of the terrible puns.

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Useful Query Store Metrics

Published 2025-06-16 by Kevin Feasel

Jared Poche gives us five:

Query Store is my favorite way to gather information about problem queries and plans, and I wanted to share some information on the useful metrics I use most.

The first two are obvious, but there’s a difference between them. The last two are not obvious but offer an unusual utility. I also wanted to explain why I use logical reads and mostly ignore physical reads.

Read on for Jared’s list.

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Fixing OPTIMIZATION_REPLAY_FAILED Errors in SQL Server

Published 2025-05-01 by Kevin Feasel

Kendra Little fixes a problem:

Forcing plans with Query Store can be a powerful tool—until it mysteriously fails. In real production systems, plan forcing sometimes just… doesn’t work. One common culprit is the cryptic OPTIMIZATION_REPLAY_FAILED error.

If you’re hitting OPTIMIZATION_REPLAY_FAILED, try re-forcing the plan using @disable_optimized_plan_forcing=1.

Click through for a summary of the problem and additional helpful information on the issue.

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SQL Server Execution Plan Analysis Features

Published 2024-12-11 by Kevin Feasel

Hugo Kornelis looks back at some nice additions to SQL Server:

It’s December. The last month of the year, and hence also the last T-SQL Tuesday of the year. Edition 181 is hosted by Kevin Chant. His chosen topic for this episode is to have us talk about which SQL Server announcement excited us the most.

This posed a bit of a problem for me. The only truthful answer here is that I have never been as excited about an announced new feature as when the Query Store was announced. But I also realized that I don’t have much to write about the Query Store, except how awesome it is. Okay, I could go on a full explanation, but many others do that much better, and have already done so. So that doesn’t leave much for me.

And that’s why I’ll also include my second favorite announcement.

Read on for a little bit around Query Store, followed up with coverage of several interesting additions to SQL Server over the years.

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The Joy of Query Store

Published 2024-12-11 by Kevin Feasel

Andy Brownsword gets into the spirit:

Reviewing performance for a SQL database over time can be a challenge without hand crafted tooling or using external monitoring apps. This isn’t about putting fires out, we’re looking at proactive monitoring and taking action for incremental improvements.

The Query Store comes to the rescue by providing built-in insights into key performance metrics over time. We can use different combinations of them to better understand how the database is working.

Query Store isn’t perfect, but it’s very good solution to an extremely common problem.

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