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.

Cool Query Hints

Last Updated January 22, 2020

Brent Ozar

T-SQL

The SQL Server documentation has a pretty cool list of query hints: Yeah, I surf in dark mode. I’m a dark kinda guy. But wait – what’s that colored box? ENHANCE! I could make jokes here, but … every single thing in that caution is true. SQL Server really does typically select the best execution…

Where Should You Tune Queries: Production, Staging, or Development?

Last Updated January 22, 2020

Brent Ozar

Execution Plans

The #1 fastest way to tune queries is in the production database, on the production server. I know. Put the knife down. You’re not happy about that, but hear me out: I’m specifically talking about the fastest way to tune queries. In production, you can guarantee that you’re looking at the same data, hosted on the…

Building SQL ConstantCare: Let’s Tune an Index in Postgres.

Last Updated January 14, 2020

Brent Ozar

Indexing, PostgreSQL

This week, our SQL ConstantCare® back end services started having some query timeout issues. Hey, we’re database people – we can do this, right? Granted, I work with Microsoft SQL Server most of the time, but we host our data in Amazon Aurora Postgres – is a query just a query and an index just…

Performance Tuning Means 3 Things

Last Updated January 8, 2020

Brent Ozar

Processes and Practices

Managing what requests are made Managing the efficiency of each request Managing the hardware capacity available to satisfy requests And that’s it. In the grand scheme of things, those are the only 3 knobs you get. Oh sure, from the outside, performance tuning looks more complicated than that, but at the end of the day,…

Can SELECT * Make a Query Go…Faster?!?

Last Updated January 7, 2020

Brent Ozar

Execution Plans

Most of the time, you’ll hear advice that you should select as few columns as possible so that SQL Server can do less work. However, one of my clients hit a neat edge case scenario where SELECT * queries actually ran faster than picking a subset of columns. I can’t share the exact query, but I…

Building SQL ConstantCare®: Which Recommendations Do People Mute?

Last Updated January 9, 2020

Brent Ozar

SQL ConstantCare

Our SQL ConstantCare® service sends you daily recommendations for specific tasks that will improve your SQL Server’s health and performance. Next to each recommendation, there’s a Mute link that you can click on to either mute the recommendation entirely, or mute it for specific databases, indexes, or queries: When we brought out that feature last…

Three Reasons to (Temporarily) Change Max Worker Threads

Last Updated January 7, 2020

Brent Ozar

Configuration Settings

When you go to the deli, there’s a “take a number” dispenser where you tear off a number and wait for your number to be called. If you walked into a deli and you saw 50 people lined up all waiting their turn, and you went to take a number and the dispenser was completely…

[Video] You shouldn’t dynamically create/alter/drop triggers.

Last Updated January 6, 2020

Brent Ozar

T-SQL

Let’s get one thing out of the way first: this isn’t about the relative good or evil of triggers. I kinda like triggers, in fact – they’re good for enforcing business logic in a hurry when you can’t redo code across an entire application. Sure, in a perfect world, we’d always have the code do…

The 2020 Data Professional Salary Survey Results Are In.

Last Updated January 5, 2020

Brent Ozar

Salary

We asked what you make, and 1,734 of you in 63 countries answered. Altogether, you made $170,753,936 this year. Damn, y’all are bringing home the bacon! Download the 2020, 2019, 2018, & 2017 results in Excel. A few things to know about it: The data is public domain. The license tab makes it clear that…

My 11 Favorite 2019 Blog Posts

Last Updated December 29, 2019

Brent Ozar

Company News

Yesterday, I showed the stuff you read the most, but enough data – now, let’s talk about feelings. These were the 11 posts I remember with the most fondness, in date order. I did indeed like some of the ones from yesterday’s list a lot, but I’m going to set those aside. Erik and Tara…

Your Ten Favorite Blog Posts from 2019

Last Updated December 29, 2019

Brent Ozar

Company News

Here are the 2019 posts you visited the most this year: 10. The Silent Bug I Find in Most Triggers – Once you know how to recognize this bug, you’ll see it everywhere. I wrote the post as an interactive Azure Data Studio notebook, something I thought I’d be doing a lot in 2019, but…

How to Make SELECT COUNT(*) Queries Crazy Fast

Last Updated December 22, 2019

Brent Ozar

Columnstore Indexes, Execution Plans

When you run a SELECT COUNT(*), the speed of the results depends a lot on the structure & settings of the database. Let’s do an exploration of the Votes table in the Stack Overflow database, specifically the 2018-06 ~300GB version where the Votes table has 150,784,380 rows taking up ~5.3GB of space. I’m going to measure…

My Home Office Studio Hardware: Winter 2019 Edition

Last Updated October 29, 2020

Brent Ozar

Home Office, Streaming

I run a lot of online training classes, and some of you who do webcasts from home might be interested to see how all this works. I did pretty well this year, so I upgraded my home office setup to sneak some expenses in on my taxes. Here’s what I’m running at the moment: Desktop:…

Voting Open for #SQLBits Sessions, and Here’s My Oddball Idea

Last Updated December 19, 2019

Brent Ozar

SQLBits

Voting is open now for SQLBits sessions, and I have to warn you that there are a LOT of sessions to choose from. Bits doesn’t just flat out take the top vote-getting sessions – they use votes as part of the session selection factor – and I don’t want you to think I’m campaigning for…

The Two Ways to Fix Non-Sargable Queries

Last Updated December 16, 2019

Brent Ozar

Execution Plans

In the database world, when we say something isn’t sargable, what we mean is that SQL Server is having a tough time with your Search ARGuments. What a sargable query looks like In a perfect world, when you search for something, SQL Server can do an index seek to jump directly to the data you…

Join Me in London for My SQLBits Pre-Con Workshop: Mastering Index Tuning

Last Updated December 20, 2019

Brent Ozar

Company News, Conferences and Classes

I’m teaching an all-new hands-on workshop, Mastering Index Tuning. I’m taking my favorite, toughest modules of my 3-day online class and condensing them down into a 1-day workshop. You’ll learn quick, easy techniques to use the right nonclustered indexes, filtered indexes, indexed views, and columnstore indexes that will work on SQL Server 2019, 2017, 2016,…

Microsoft’s Guidance on How to Set MAXDOP Has Changed

Last Updated December 16, 2019

Brent Ozar

Production Database Administration

For years, SQL Server’s Maximum Degree of Parallelism (MAXDOP) – the number of cores that a parallel query could use – defaulted to 0, meaning unlimited. This led to rampant CXPACKET waits because queries went wild with parallelism. Overly wild, like me after six shots of tequila within an hour wild. (It’s not my fault:…

Are You Underpaid? Let’s Find Out: The Data Professional Salary Survey is Open.

Last Updated January 5, 2020

Brent Ozar

Salary

It’s time for our annual salary survey to find out what data professionals make. You fill out the data, we open source the whole thing, and you can analyze the data to spot trends and do a better job of negotiating your own salary: I make my query bucks the hard way Take the Data…

Upsizing the SQL ConstantCare® Database Servers

Last Updated December 7, 2019

Brent Ozar

Amazon Web Services (AWS), SQL ConstantCare

If you’re looking for SQL Server news, just skip this post. I’m going to talk about general business & capacity planning type stuff here today. Our SQL ConstantCare® customers install an app that polls diagnostic data from their SQL Servers and Azure SQL Databases, upload it to us daily, and then automatically get advice on…

What Should We Change About This Year’s Data Professional Salary Survey?

Last Updated December 2, 2019

Brent Ozar

Salary

Every year, we run a Data Professional Salary Survey here. Thousands of y’all have answered – here are the past results in Excel – and it helps everybody get a better idea of how overpaid they are. (Did I word that right?) Here are the questions I’m planning to ask this year: What’s your total…