Posts by Brent Ozar

In the last Query Exercise discussion, we hit a performance wall when we were trying to quickly find questions with a specific tag. We threw up our hands and said it’s time to make database changes, but we had a few restrictions: We have a lot of existing code that uses the Posts.Tags column That…

#TSQL2sday Invitation: Describe the Most Recent Issue You Closed.

Last Updated December 30, 2023

Professional Development

T-SQL Tuesday is a monthly blogothon where we get together and write about a different topic. I’m hosting this month’s episode. Your readers wonder what kinds of jobs are out there in the database world, what exactly it is that you do, and what your daily grind is like. While it’d be cool to cover all…

Office Hours: PowerBI & Fabric Q&A with Eugene Meidinger

Last Updated January 31, 2024

Today’s Office Hours has a different topic. Eugene Meidinger dropped by to answer your business intelligence questions. Follow Eugene on YouTube and TikTok Subscribe to his 5-link weekly newsletter Check out Eugene’s new Power BI classes Read Eugene’s blog posts PowerBI and Fabric Q&A with Eugene MeidingerWatch this video on YouTube 00:00 Start 01:35 Tim:…

Who’s Hiring in the Microsoft Data Platform Community? February 2024 Edition

Last Updated January 5, 2024

Who's Hiring

Is your company hiring for a database position as of February 2024? Do you wanna work with the kinds of people who read this blog? Let’s set up some rapid networking here. If your company is hiring, leave a comment. The rules: Your comment must include the job title, and either a link to the…

Finding Tagged Questions Faster: Answers & Discussion

Last Updated February 23, 2024

Your query exercise was to take this Stack Overflow query to find the top-voted questions for any given tag: Transact-SQL SELECT TOP 100 * FROM dbo.Posts WHERE Tags LIKE '%<sql-server>%' ORDER BY Score DESC; 1234 SELECT TOP 100 *FROM dbo.PostsWHERE Tags LIKE '%<sql-server>%'ORDER BY Score DESC; That’s currently using this index in its execution plan:…

Free Video Training: Estimation and Statistics by Dave Ballantyne

Last Updated January 30, 2024

Statistics, Videos

It’s hard to find good 400-500 level SQL Server training at any price, let alone free. Dave Ballantyne’s past sessions from SQLBits are great examples of those. Today, I’m going to review Dave’s most recent session on Estimation and Statistics. It’s from 2015, but it’s still very relevant today. If you want to jump past…

What PowerBI Questions Do You Have for Eugene Meidinger?

Last Updated January 29, 2024

Data Science

Eugene Meidinger, aka SQLGene.com, makes Power BI concepts easy and accessible. He’s got a free introduction to Power BI performance tuning here. People come to him with questions like: What kind of tools are there for performance tuning Power BI? Where should I do my logic: SQL, Power Query, or DAX? What are some best…

Query Exercise: Find Tagged Questions Faster.

Last Updated July 7, 2025

For this week’s Query Exercise, we’re going to start with an existing query that has performance problems from time to time, depending on how it’s used. This query’s goal is to find the top-voted Stack Overflow questions for any given tag – for example, here are the top-voted questions tagged “sql-server”. What are tags? I’m…

Finding the Best Time for Maintenance: Answers & Discussion

Last Updated January 22, 2024

Your Query Exercise was to find the best time to do database maintenance by querying the Users table, looking for a one-hour window with the lowest number of created users. We kept this one pretty simple by looking at the data in just one table, and we didn’t hassle with time zones. We just wanted…

Save 10% on SQLBits 2025 Registration with Coupon Code OZAR102025.

Last Updated April 13, 2025

SQLBits

Going to the SQLBits conference? Whether you’re registering in-person or attending virtually, save 10% on your ticket with discount code OZAR102025. During the checkout process, look for this: And save yourself some quick bucks. The screen will refresh after you hit Apply, so make a note of the price before & after. You’re welcome! Register…

[Video] Office Hours: The Question is Not the Problem Edition

Last Updated January 8, 2024

I answer your top-voted Azure SQL DB and SQL Server questions from https://pollgab.com/room/brento and lose my temper about what you’re doing. Office Hours: The Question Isn't The Problem EditionWatch this video on YouTube Here’s what we covered: 00:00 Start 00:40 Mattia: Has bulk logged recovery model ever got you across the finish line? If so,…

Query Exercise: Find the Best Time for Maintenance

Last Updated January 24, 2024

If we’ve gotta take the database down for maintenance – perhaps a version upgrade, perhaps upgrading our own code, maybe scaling up the hardware – when’s the best time to do it? For this week’s query exercise, the business has asked us to identify 3 1-hour periods with the least user activity, in this format:…

Find Posts with the Wrong CommentCount: Answers & Discussion

Last Updated January 14, 2024

Your Query Exercise was to find denormalization accuracy problems: checking the accuracy of a reporting column, Posts.CommentCount. There were two parts: finding the top 100 most problematic Posts with the biggest variances, and thinking about a long term solution to keep the CommentCount accuracy as high as practical. Question 1: Finding the Problematic Posts Your…

We’re Starting to Automate Testing for the First Responder Kit.

Last Updated January 10, 2024

First Responder Kit

Brent says: It’s really funny how the world works. I wrote what you see below in December 2023 and scheduled it for publication on January 16th (today), hoping to get help from the community to get this process started. On January 9, before the post went live, David Wiseman submitted a pull request with the…

[Video] Office Hours: Ask Me Anything About the Microsoft Data Platform

Last Updated January 4, 2024

Forgive the hoarse voice – I’m recovering from something COVID-ish. I went through your top-voted questions from https://pollgab.com/room/brento and did my best: Office Hours: Ask Me Anything About Azure and SQL ServerWatch this video on YouTube Here’s what we covered: 00:00 Start 03:03 DBANoob: We have EF code that creates randomly generated temp table names…

Query Exercise: Find Posts with the Wrong CommentCount

Last Updated January 24, 2024

For 2024, I’m trying something new: weekly homework challenges! For this week’s query challenge, we’re going to do some data validation. Pop open the Stack Overflow database and check out the CommentCount column on the Posts table: In theory, that’s a fast way to check how many Comments a particular Post has, without querying the…

Find Foreign Key Problems: Answers & Discussion

Last Updated July 7, 2025

Your Query Exercise was to find foreign key problems: data that might stop us from successfully implementing foreign keys in the Stack Overflow database. Question 1: Write queries to find the problematic data. Montro1981’s thorough answer broke the challenge into two parts: first, check to see if there is ANY bad data, and if so,…

Announcing the 2024 Data Professional Salary Survey Results.

Last Updated January 4, 2024

Salary

This is the 8th year now that we’ve been running our annual Data Professional Salary Survey, and I was really curious to see what the results would hold this year. How would inflation and layoffs impact the database world? Download the raw data here and slice & dice it to see what’s important to you. Here’s…

Query Exercise: Find Foreign Key Problems

Last Updated January 10, 2024

For 2024, I’m trying something new: weekly homework challenges! For this week, let’s say we’ve decided to implement foreign keys, and we need to find data that’s going to violate our desired keys. We’re going to use the Stack Overflow database, and we’ll focus on these 3 tables: dbo.Users table: with Id column as its…

[Video] Office Hours: Oddball Questions Edition

Last Updated December 30, 2023