Clustered and nonclustered indexes, keys, included columns, and access paths.
113 associated posts109 primary posts
In my free How to Think Like the Engine class, I gloss over the entire concept of B-trees and just hand-wavily say "SQL Server can seek to the page that has the row you're looking for." That's always kinda bothered me, so I finally gave in to temptation and whipped up an animated example of a clustered index on the Users table:
Well, maybe mountain is a bit of a strong word, but it's one of the highest elevation home sites in Las Vegas, with beautiful views over the valley, the Strip, the airport, and the surrounding mountains. Let's go through your top-voted questions from https://pollgab.com/room/brento while taking in the view - and you can move the camera around, since this is an Insta360 video.
The official Azure SQL Dev's Corner blog recently wrote about how to enable soft deletes in Azure SQL using row-level security, and it's a nice, clean, short tutorial. I like posts like that because the feature is pretty cool and accomplishes a real business goal. It's always tough deciding where to draw the line on how much to include in a blog post, so I forgive them for not including one vital caveat with this feature.
Before SQL Server 2025, if you want to store JSON data in Microsoft SQL Server or Azure SQL DB, and you want fast queries, the easiest way is to:
Store the data in an NVARCHAR(MAX) column (because the native JSON datatype didn't arrive until SQL Server 2025)
Add a computed column for the specific JSON keys we'll want to query quickly
Index those keys
Query it using the JSON_VALUE function
Wanna hear about my worst job interviews? I drove up to 8,000 feet where it's 30 degrees colder than Las Vegas to bring you these answers to your top-voted questions from https://pollgab.com/room/brento. The audio's a little odd on here because it was really windy, and I had to use noise reduction in post-production.
I've always wanted to see the Barcelona Pavilion by Mies van der Rohe, and by happy coincidence, I ended up walking right past it while visiting Barcelona! It's one of the most important beginnings of modern architecture, and I loved it. I brought you along with me and talked through your top-voted questions from https://pollgab.com/room/brento.
While recovering from a nasty cold, I took your top-voted questions from https://pollgab.com/room/brento.
https://www.youtube.com/watch?v=Et1mNyC1lIk
You're looking at a wide table with 100-200 columns.
Years ago, it started as a "normal" table with maybe 10-20, but over the years, people kept gradually adding one column after another. Now, this behemoth is causing you problems because:
It's spooky time again! I visited Salem, Massachusetts again this year, this time for a friend's wedding. I ended up in the same spot next to the Charter Street Cemetery that I filmed at last year! I went through your top-voted questions from https://pollgab.com/room/brento.
https://www.youtube.com/watch?v=Q4WtTm3O4bA
Let's start with the Stack Overflow database (any size will work), drop all the indexes on the Users table, and run a delete:
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I went through your top-voted questions from https://pollgab.com/room/brento plus hit live ones from the TikTok viewers.
https://www.youtube.com/watch?v=XDx-OnTHezA
While taking a dip in Cabo, I went through your top-voted questions from https://pollgab.com/room/brento.
https://www.youtube.com/watch?v=OaHImrIMM6Y
Today's Office Hours comes from a very different office! I climbed into the hot tub to review your top-voted questions from https://pollgab.com/room/brento. Don't worry, the webcast is completely safe for work.
https://www.youtube.com/watch?v=e1jg1_uHBxM
In last week's Query Exercise, our developers had a query that wasn't going as fast as they'd like:
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The query had an index, but SQL Server was refusing to use the index - even though the query would do way less logical reads if it used the index. You had 3 questions to answer:
Why yes, I'm wearing the same shirt as the video from "yesterday". Why do you ask? Stop paying attention to that, and check out the top-voted questions from https://pollgab.com/room/brento.
https://youtu.be/_vpHLQYpARM
Despite its location, Hammerfest, Norway attracts countless tourists eager to see the festival celebrating one of the world's favorite rappers. Did I get that right? I'm not sure I got that right. There's also fierce competition for the title of northernmost town: nearby Honningsvåg Norway also wants that claim, but with a population of only…
There are only a couple weeks left in this summer's marathon of Office Hours sessions, which means there's limited time left to ask your toughest database problems (not trivia questions) at https://pollgab.com/room/brento.
https://www.youtube.com/watch?v=ZVZAcE4aJPE
A lot of today's questions from https://pollgab.com/room/brento have a common theme, but it's just a coincidence:
https://www.youtube.com/watch?v=x2Tm_BHXT68
It was a dark and stormy morning, on the last day of my Panama Canal cruise. Before I perished, I sat down to answer your top-voted questions from https://pollgab.com/room/brento.
https://youtu.be/lAMRoB1LyWE
While waiting for the dry cleaner to open, I went live to stream a quiet session going through a bunch of y'all's questions from https://pollgab.com/room/brento.
https://youtu.be/1rYG0laQpOU
