Brent Ozar, Author at Brent Ozar Unlimited®

Brent Ozar

1687 posts

https://www.brentozar.com

I make Microsoft SQL Server go faster. I love teaching, travel, and laughing. I live in California with my wife Erika.

Research Paper Week: Constant Time Recovery in Azure SQL DB

August 23, 2019

Brent Ozar

Azure SQL DB, Backup and Recovery

No Comments

Let’s finish up Research Paper Week with something we’re all going to need to read over the next year or two. I know, it says Azure SQL DB, but you boxed-product folks will be interested in this one too: Constant Time Recovery in Azure SQL DB by Panagiotis Antonopoulos, Peter Byrne, Wayne Chen, Cristian Diaconu, Raghavendra…

Research Paper Week: In-Memory Multi-Version Concurrency Control

August 22, 2019

Brent Ozar

SQL Server

If you’ve been doing performance tuning for several years, or graduated from my Mastering Server Tuning class, you’ve come across Read Committed Snapshot Isolation, aka RCSI, aka multi-version concurrency control, aka MVCC, aka optimistic concurrency. It’s not the way SQL Server ships by default, although it is the default for Azure SQL DB, and it’s part…

Research Paper Week: Automatic Indexing in Azure SQL DB

August 21, 2019

Brent Ozar

Architecture, Azure SQL DB, Indexing

Before I give you the link to the next research paper in this week’s series, I wanna give you a few questions to think about: If you had to build something to automatically add indexes to SQL Server databases, where would you start? What data would you use to make your decisions? How would you…

Research Paper Week: Query Execution in Column-Oriented Database Systems

August 20, 2019

Brent Ozar

Columnstore Indexes

This week, I’m sharing some of my favorite papers that I’ve read. Sometimes they’re about future technologies that haven’t shipped yet – and may never ship! Sometimes, like this one, they’re not from Microsoft at all, but from someone else in the industry who’s explaining a problem that we face in SQL Server. SQL Server…

Research Paper Week: Plan Stitch: Harnessing the Best of Many Plans

August 19, 2019

Brent Ozar

Execution Plans

Those of you who follow me on Instagram, Twitter, or Facebook know I’m taking most of August off for vacation. Erika and I spent the last couple of weeks in Telluride, had a brief stop in Sacramento for SQL Saturday, and this week we’re touring wineries in Napa and Sonoma. As part of recharging, I…

DBA Training Plan 12: What Query Plans Are In Cache?

August 15, 2019

Brent Ozar

DBA Training Plan, Execution Plans, sp_BlitzCache

In the last episode, while talking about the basics of executing queries, I said that SQL Server caches execution plans in memory, reusing them whenever the same query gets executed again. I’ve also talked about the dynamic management views (DMVs) that let you query what’s in SQL Server’s memory. Let’s put those two things together…

DBA Training Plan 11: The Basics of Executing a Query

August 14, 2019

Brent Ozar

DBA Training Plan, Execution Plans

Up til now in the DBA Training Plan, we’ve been taking inventory of our servers, making sure the data’s well-protected, and understanding the basics of how the data’s stored in indexes inside those data files. Now, let’s start looking at performance, and let’s start by zooming really far out to think about how SQL Server…

DBA Training Plan 10: Managing Index Fragmentation

August 13, 2019

Brent Ozar

DBA Training Plan, Index Maintenance

In the last episode, we looked at your index designs with the output of sp_BlitzIndex. You might have gotten a little overwhelmed what with all the different warnings (and all the learning resources!) You might have thought, “Is there an easier way?” “Is there a way I can just run a job, and have something…

DBA Training Plan 9: My 3 Index Guidelines

August 12, 2019

Brent Ozar

DBA Training Plan, Indexing

In our last episode, we used sp_BlitzIndex @Mode = 2 to get to know the contents of our database, sorted our indexes from biggest to smallest, and started asking questions about leftover backup tables that we probably didn’t need to keep around anymore. Now that you’ve taken out the trash, let’s have a closer look…

DBA Training Plan 8: What’s Inside Your Own Databases

August 6, 2019

Brent Ozar

DBA Training Plan, Indexing

No Comments

In the last episode of the DBA Training Plan, we talked about what’s inside the MDF file: a series of pages that store a database’s tables. Now, it’s time to check out the contents of YOUR database to understand what’s using the most space, what’s getting used the most often, and what you might be…

“But NOLOCK Is Okay When The Data Isn’t Changing, Right?”

August 5, 2019

Brent Ozar

Development

I’ve already covered how NOLOCK gives you random results when you’re querying data that’s changing, and that’s a really powerful demo to show folks who think NOLOCK is safe to use in production. However, I’ve gotten a question from several users: But I’m querying data that isn’t changing – sure, OTHER rows in the table…

What The Consultant Toolkit Does

August 1, 2019

Brent Ozar

Consultant Toolkit

It’s one thing for me to tell you how much easier The Consultant Toolkit makes my job and how clients love how much I can tell them about their server during the initial sales call – but it’s another thing to hear it from a happy customer: Thought I would share a story, with my…

DBA Training Plan 7: How SQL Server Stores Stuff in MDF Files

July 31, 2019

Brent Ozar

DBA Training Plan, Indexing

So far in the DBA Training Plan, we’ve been working hard to make sure the contents of our MDF files are backed up, corruption-free, and secured. Now, uh…what’s actually inside them? Inside each of your database data files (MDFs, although technically you can use any extension you want, even PDF or MP3), SQL Server stores…

DBA Training Plan 6: How to Monitor Drive Space

July 30, 2019

Brent Ozar

DBA Training Plan, Monitoring

Don’t. It’s not your job. No, seriously, hang on a second. I’m not saying that you should ever say things like “It’s not my job,” but I do want you to understand when you should avoid reinventing the wheel. Your Windows administrators should be monitoring every Windows server you have, making sure it doesn’t run…

Podcast: Data Driven Inteview w/Me

July 30, 2019

Brent Ozar

SQL Server

No Comments

I had the pleasure yesterday of spending an hour chatting with Andy Leonard and Frank La Vigne for the Data Driven podcast. Some of the questions they asked me include: How did you find your way into data? What’s your favorite part of your current gig? Complete this sentence: when I’m not working, I enjoy…

Adam Machanic, Japanese Snack Connoisseur

sp_WhoIsActive Is Now Open Source.

July 29, 2019

Brent Ozar

Tools

Adam Machanic, Japanese Snack Connoisseur If you’re still using sp_who, sp_who2, and Activity Monitor, listen up: there’s a great free replacement, and it’s now open source, too! sp_WhoIsActive is a much more powerful way to analyze what’s happening right now on your server. Here’s what you need to know: sp_WhoIsActive’s home on Github – releases…

DBA Training Plan 5: Knowing Who Has Access

July 24, 2019

Brent Ozar

DBA Training Plan

Who can get you fired? Run our free sp_Blitz stored procedure on one of your production servers and pay particular attention to the Security section of the results. It lists the logins who have been granted the sysadmin or security admin roles. Don’t think of them as logins. Think of them as people who can get…

DBA Training Plan 4: Checking for Corruption

July 23, 2019

Brent Ozar

CHECKDB and Corruption, DBA Training Plan

You would think that when SQL Server writes your data to disk, it’s totally safe. Forever. You would be wrong. It’s almost like there are gremlins out to get you, purposely trying to trash your data. In the really old days, it was problems with magnetic hard drives. Later, it was buggy shared storage arrays.…

DBA Training Plan 3: Treat Your Servers Like Cattle, Not Like Pets

July 22, 2019

Brent Ozar

Backup and Recovery, DBA Training Plan

In our last post in this series, I talked about why you should be using Ola Hallengren’s maintenance script for backups and sp_DatabaseRestore for faster restores. These two tools have implications for how you build, back up, recover, and fail over your SQL Server. There’s a saying in the cloud: treat your servers like cattle,…

Nines don't matter if users aren't happy

DBA Training Plan 2: Backups (And More Importantly, Restores)

July 17, 2019

Brent Ozar

Backup and Recovery, DBA Training Plan

When I first started out as a SQL Server DBA, I thought things were going well as long as the backup jobs ran successfully. I’d go into SQL Server Agent every now and then, make sure they were still running, and … that was the end of it. I figured if disaster ever struck, I’d…

Posts by Brent Ozar