Posts by Brent Ozar

Brent Ozar

2781 posts

https://www.brentozar.com

I make Microsoft SQL Server go faster. I love teaching, travel, cars, and laughing. I'm based out of Las Vegas. He/him.

Why Ordering Isn’t Guaranteed Without an ORDER BY

Last Updated April 11, 2020

Brent Ozar

Indexing, T-SQL

If your query doesn’t have an ORDER BY clause, you can’t reliably predict the order of your results over time. Sure, it’s going to look predictable at first, but down the road, as things change – the indexes, the table, the server’s configuration, the size of your data – you can end up with some ugly…

[Video] Altering Datatypes With (Almost) No Downtime

Last Updated August 21, 2025

Brent Ozar

Development

Sometimes, your INT columns run out of space, and you need to alter them to be a larger datatype, like BIGINT. (Don’t forget you can always set the identity seed to -1, and increment -1, if you’re okay with ever-decreasing negative IDs – and I use this as a short-term workaround while I prepare for…

What’s Your Favorite SQL Server Interview Question? Here’s Mine.

Last Updated November 26, 2020

Brent Ozar

Interviewing

“Out of the stuff on your resume, what are you the proudest of, the most excited about? When I’m interviewing a candidate for one of my clients, I’ll usually start with this question to help understand the resume. See, recruiters seem to actively encourage folks to keyword stuff their resume: to dump in everything and…

My Home Office Studio Hardware: Spring 2020 Edition

Last Updated October 29, 2020

Brent Ozar

Home Office, Streaming

When I last blogged about my home office setup in December, I’d just invested in a new massive beast of a desktop: a Mac Pro with a 16 cores, 96GB RAM, and a AMD Radeon Pro Vega II 32GB. Now it’s time to put that horsepower to work. In the past, I’ve used GoToWebinar for…

Want SQL Server Training? Copy/Paste This Email To Your Boss.

Last Updated April 7, 2020

Brent Ozar

Company News, Conferences and Classes

Well, that escalated quickly, huh? Just a few short months ago, we were all making plans about what we wanted to learn in 2020. We sketched out our goals, our conference plans, maybe even how we wanted to do our first user group presentations or SQL Saturday presentations. These days: The events you wanted to…

[Video] How Can I Measure If My Database Does More Reads Than Writes?

Last Updated April 5, 2020

Brent Ozar

Production Database Administration, Videos

When someone asks you, “Is this database read-intensive or write-intensive?” you probably look at sys.dm_io_virtual_file_stats to measure the file activity – but that isn’t really correct. After all, your users run a lot of queries all day that are simply satisfied from the buffer pool. SQL Server caches your data so it doesn’t have to hit…

Announcing Two Free Live Fundamentals Courses This Wednesday & Thursday

Last Updated April 8, 2020

Brent Ozar

Conferences and Classes

During the quarantines, I’m trying to keep you busy with free online training. Last week, I unveiled the new free Quest Database Training Days, and this week, I’ve got another one. I’m going to teach my Fundamentals classes live, free! Wednesday, Fundamentals of Index Tuning – 9:00-5:00 Eastern (13:00-21:00 UTC) – click to see in your own…

[Video] Watch Brent Work on sp_Blitz

Last Updated April 5, 2020

Brent Ozar

sp_Blitz, Videos

During the quarantines, I’m looking for new ways to help you level up for free. I decided to start live-streaming whenever I’m working on things I can share with you publicly. I wanted to add a new check to sp_Blitz, so I figured I’d do it live on camera while you watch, and talk you…

Congrats. Y’all Raised $8,919 for Doctors Without Borders in March.

Last Updated April 1, 2020

Brent Ozar

Company News

I hate posting things on April 1, but there’s no laughing here, only cheering. During our March quarantine sale, I donated 10% of all sales to Doctors Without Borders. I’m proud to announce that y’all raised $8,919 to provide lifesaving medical humanitarian care in over 70 countries. I’m excited to see you in class. Y’all…

What Does This Button Do? Wrong Answers Only.

Last Updated March 27, 2020

Brent Ozar

Humor

126

One of my favorite memes is Wrong Answers Only, where you show something and people have to answer incorrectly, like this and this and this. So now it’s your turn: you’re in SSMS, you right-click on a database, and go into Tasks: What does that bottom right task do? Wrong answers only.

This? It's just coffee, as far as you need to know.

Announcing Quest Database Training Days: Free Live Training with Me, Janis, and Pinal

Last Updated March 27, 2020

Brent Ozar

Conferences and Classes

During the quarantines, I’m trying to find as many ways as possible to get y’all free training. Today & tomorrow are the last days that you’ve got free access to the recordings of my Fundamentals of Index Tuning and Fundamentals of Query Tuning classes – get those while you can, because they’ll disappear when March…

[Video] What Percent Complete Is That Index Build?

Last Updated March 24, 2020

Brent Ozar

Index Maintenance, SQL Server 2017, Videos

SQL Server 2017 & newer have a new DMV, sys.index_resumable_operations, that show you the percent_completion for index creations and rebuilds. It works, but…only if the data isn’t changing. But of course your data is changing – that’s the whole point of doing these operations as resumable. If they weren’t changing, we could just let the operations…

Updated First Responder Kit and Consultant Toolkit for March 2020

Last Updated March 24, 2020

Brent Ozar

First Responder Kit Updates

In the immortal words of “Orange” Julius Caesar as written by Shake’s peer, “Beware the bugs of March.” It took us 2,064 years, but we’ve finally fixed those bugs, plus added a couple of new features. To get the new version: Download the updated FirstResponderKit.zip Azure Data Studio users with the First Responder Kit extension:…

The First Time I Had to Restore a Database

Last Updated March 24, 2020

Brent Ozar

Backup and Recovery

Not the exact same time frame, but not that far off. I remember it really clearly. In the mid 1990s, long, long before I went into IT as a career, I was working at a photo studio in Muskegon, Michigan. They specialized in high school class photos, and they did a LOT of ’em. Every morning,…

“Working” From Home? Watch A Bunch of Free SQL Server Videos on YouTube.

Last Updated March 13, 2020

Brent Ozar

Videos

You’re new at this working from home thing, and you’re trying to put Game of Thrones up on a second monitor while you work? Listen, that’s not gonna play out well. You’re gonna get distracted and you’re not gonna get any work done. Instead, if you’re gonna have something in the background, learn about SQL…

How to Track Performance of Queries That Use RECOMPILE Hints

Last Updated May 26, 2020

Brent Ozar

Parameter Sniffing, Query Store (QDS), sp_BlitzCache

Say we have a stored procedure that has two queries in it – the second query uses a recompile hint, and you might recognize it from my parameter sniffing session: Transact-SQL CREATE OR ALTER PROC dbo.usp_SearchUsers @Reputation INT AS BEGIN /* Query 1, always the same: */ SELECT COUNT(*) FROM dbo.Users; /* Query 2, recompiles…

How COVID-19 Affects Conferences

Last Updated March 11, 2020

Brent Ozar

Conferences and Classes

SQLBits just postponed their event, and I’m stepping out of SQL Saturday Iceland as well. I’ve had the unusual position of being a conference attendee, speaker, and sponsor, all at different times of my life, so I wanted to do a quick brain dump explaining some of the gotchas involved behind the scenes. Canceling a…

Things to Consider When SQL Server Asks for an Index

Last Updated March 1, 2020

Brent Ozar

Indexing, SQL ConstantCare

One of the things I love about SQL Server is that during query plan compilation, it takes a moment to consider whether an index would help the query you’re running. Regular blog readers will know that I make a lot of jokes about the quality of these recommendations – they’re often incredibly bad – but…

Making TRY_CAST and TRY_CONVERT Queries Faster with Indexed Computed Columns

Last Updated March 1, 2020

Brent Ozar

Computed columns, Execution Plans, T-SQL

I know this is gonna sound crazy, but let’s say you had a table where people stored all kinds of things in one column: dates, integers, file names, sale prices, file names, you name it. And let’s say your application frequently ran a query looking for dates in that column, like this: Transact-SQL SELECT *…

How to Find Cool Questions and Answers on DBA.StackExchange.com

Last Updated March 4, 2020

Brent Ozar

Stack Overflow Database

DBA.StackExchange.com is a Stack Overflow site that’s specifically targeted at database administrators. There tend to be some pretty interesting questions in there – not just for SQL Server, but all kinds of databases – but at the same time, there’s also a lot of noise. To help find fun questions, I use The Power of…