Posts by Brent Ozar

Brent Ozar

2783 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.

Setting MAXDOP During SQL Server 2019 Setup

Last Updated May 23, 2019

Brent Ozar

SQL Server 2019

Just a short note – in SQL Server 2019, the setup process has a new MAXDOP tab: The hyperlink about MAXDOP configuration points here. I did a few quick test installs: 4 cores gave me a MAXDOP 4 8 cores offered MAXDOP 8 12 cores offered MAXDOP 6 Historically, the 0 default meant unlimited cores.…

My classes have really sucked lately, and I apologize.

Last Updated May 22, 2019

Brent Ozar

Company News

I teach my Mastering classes in a regular rotation: Mastering Index Tuning, then Mastering Query Tuning, then Mastering Server Tuning. I go 1-2-3 like that because they build on each other, and I repeat ’em over and over through the year so people can gradually make progress. I just finished another rotation, so it’s time…

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

9 Tips for Faster SQL Server Applications

Last Updated May 23, 2019

Brent Ozar

Development

Wanna make your SQL Server applications go faster? Here are 9 simple tips that will give you a better chance for success. They’re not carved in stone, but they’re a good place to start. Query Design Tips 1. Code for readability first. The easier your query is for humans to understand, the more likely SQL…

Does the Rowmodctr Update for Non-Updating Updates?

Last Updated May 20, 2019

Brent Ozar

Index Maintenance

Get Notebook – FAQ Update May 20 – make sure to read to the end for an update. Okay, look, it’s a mouthful of a blog post title, and there are only gonna be maybe six of us in the world who get excited enough to check this kind of thing, but if you’re in…

Building SQL ConstantCare®: Letting You Mute Recommendations

Last Updated May 16, 2019

Brent Ozar

SQL ConstantCare

When we first launched SQL ConstantCare®, I saw it as a mentoring service, not a monitoring service. I wanted to give you advice that I’d learned the hard way across managing lots of systems. With that in mind, I told users as they came onboard, “If there are any recommendations that you want me to…

Why Order Isn’t Guaranteed Without an ORDER BY

Last Updated May 15, 2019

Brent Ozar

Execution Plans

Start with the Stack Overflow database, with no nonclustered indexes. If you’ve been playing around with demos, run my DropIndexes proc just to clear things out, which leaves the clustered indexes in place. Say you run this query: Transact-SQL SELECT TOP 100 Id, DisplayName FROM dbo.Users; 12 SELECT TOP 100 Id, DisplayName FROM dbo.Users; By default,…

Which Queries Should You Cache in the Application?

Last Updated May 9, 2019

Brent Ozar

Development

I’ve talked about how the fastest query is the one you never make, and why when you’re scaling up a database application, you probably want to start caching query results in the app tier. Caching means: Less licensing costs for SQL Server Lower CPU usage both for query execution and for compilation time Lower locking/blocking…

I’m coming to SQL Saturday Salt Lake City in August!

Last Updated May 9, 2019

Brent Ozar

SQL Server

I’m coming to Salt Lake City in August for SQLSaturday #887. On Friday, I’ll be teaching a one-day pre-con: Performance Tuning in 21 Demos – You’re a developer or DBA who wants to tune indexes and queries to make your application go faster. You don’t like learning by watching slides or reading white papers – you…

Book Review: Learn T-SQL Querying by Pedro Lopes and Pam Lahoud

Last Updated May 8, 2019

Brent Ozar

Book Reviews

Learn T-SQL Querying by Lopes and Lahoud You’ve been writing queries for at least a year or two, and you’re curious about what’s happening under the hood when SQL Server runs a query. You want to know what you can do to improve your queries, tune your indexes, and change SQL Server’s configuration settings so…

Developers: Azure SQL DB Serverless can save you money.

Last Updated July 8, 2019

Brent Ozar

Azure SQL DB

If you’ve got a database that doesn’t need to be on all the time, Azure SQL DB Serverless is in public preview now. It makes a lot of sense for those development databases you have to keep around, but don’t really want to pay for. If your database doesn’t get any queries for 6 hours,…

The Silent Bug I Find in Most Triggers

Last Updated May 6, 2019

Brent Ozar

T-SQL

Get Notebook – FAQ I don’t have a problem with triggers. They get the job done when you need to implement business logic in a hurry, and you’re not allowed to change the application. As long as you keep the number of statements to a minimum (say, 2-3), and don’t try to do something really…

Are your CPU-intensive queries running slowly? Check your VM type.

Last Updated April 28, 2019

Brent Ozar

SQL Server

When you build a VM for SQL Server in Amazon EC2, Azure VMs, or Google Compute Engine, it’s all too easy to overlook the CPU speeds that you’re getting. Most of the time, it doesn’t really matter because SQL Server isn’t usually CPU-bottlenecked: your queries are doing table scans with 16GB RAM, starving for IO throughput.…

Pop Quiz: SQL 2000 Bug or SQL 2017 Bug?

Last Updated April 28, 2019

Brent Ozar

Humor

2002: Me and Bailey, mom’s Great Dane When I was thinking about this site’s 17th birthday, I started wondering: back in 2002, what bug might I have been working with in SQL Server? I started reading back to the list of bugs fixed in SQL Server 2000 Service Pack 1, and it hit me…these bugs…

Updated First Responder Kit and Consultant Toolkit for April 2019

Last Updated December 29, 2024

Brent Ozar

First Responder Kit Updates

This month, lots of improvements and bug fixes, including checking for paused resumable index operations, Evaluation Edition expiration dates, sp_BlitzCache shows the number of duplicated plans for each query, sp_BlitzIndex will skip a list of databases for you, and more. To get the new version: Download the updated FirstResponderKit.zip Azure Data Studio users with the…

SSMS v18 and Azure Data Studio: The Golden Age of SQL Server Tooling

Last Updated April 27, 2019

Brent Ozar

Azure Data Studio

Yesterday, SQL Server Management Studio 18.0 shipped. Here’s the official announcement, the download page, and the release notes. Yes, it’s still free, and yes, they’re still adding features. Yes, they removed database diagrams and the debugger. (Update Apr 27: if you want the debugger, use Visual Studio – download.) No, SSMS 18 doesn’t run on…

BrentOzar.com is Turning 17 Years Old.

Last Updated May 8, 2019

Brent Ozar

Company News

I registered it before then, and it used to be a static HTML site, but I consider the birthday to be the first published blog post from May 7, 2002. A few fun stats: 2002 Brent: at home with a Thinkpad with a webcam module on top, reading HAL-PC Magazine 2,546 blog posts 38,614 comments…

Fixing Performance By Throwing Cloud At It

Last Updated April 22, 2019

Brent Ozar

Cloud Computing

Your databases are hosted in the cloud – either in VMs or in a database-as-a-service – and you’re having a performance emergency that’s lasted for more than a day. Queries are slow, customers are getting frustrated, and you’re just not able to get a fix in quickly. Just ask management if they want to throw…

Free SQL Server Load Testing Tools

Last Updated April 22, 2019

Brent Ozar

Load Testing

So you wanna run a load test against SQL Server. One thing I need you to understand first: you have to provide the database and the queries. Almost all of the tools in this post, except the last one, are designed to help you run queries, but they don’t include the queries. The whole idea…

15 Reasons Your Query Was Fast Yesterday, But Slow Today

Last Updated May 26, 2020

Brent Ozar

Development, Parameter Sniffing

SQLSaturday Israel 2019 speaker shirt In rough order of how frequently I see ’em: There are different workloads running on the server (like a backup is running right now.) You have a different query plan due to parameter sniffing. The query changed, like someone did a deployment or added a field to the select list.…

Which Database is Causing the Problem?

Last Updated April 16, 2019

Brent Ozar

First Responder Kit

Pick a bottle, any bottle (Moet & Chandon) You’ve got one SQL Server hosting a bunch of databases, and performance is bad. Which database should you focus on first? Here are a few ways you can pick – but keep in mind they may produce different answers, especially when you’ve got several databases that suck,…