Using query history, cached plans, and runtime data to investigate performance.
200 associated posts60 primary posts
I took a break from unpacking my SQL Saturday San Diego bags and re-packing for a Boston wedding long enough to take your top-voted questions from https://pollgab.com/room/brento.
https://youtu.be/Z0GSjyK2bps?si=5u3bMm8MYFkHViBD&t=29
I took your top-voted questions from https://pollgab.com/room/brento, including a few career-oriented ones:
https://youtu.be/GefrKvKfG1Q
I don't get it. I've given this feature one chance after another, and every time, it takes a smoke break rather than showing up for work.
The latest instance involved the recent Query Exercise where you were challenged to fix a computed column's performance. In the comments, some folks noted that performance of the query was actually great on old compat levels, like SQL Server 2008, and that it only sucked on newer compat levels like 2016 and later.
When I went through the top-voted questions at https://pollgab.com/room/brento, I didn't have all the answers today:
https://www.youtube.com/watch?v=g6fqxTPnDd0
I'm kinda weird. I get excited when I'm troubleshooting a SQL Server problem, and I keep hitting walls.
I'll give you an example. A client came to me because they were struggling with sporadic performance problems in Azure SQL DB, and nothing seemed to make sense:
Sometimes y'all post questions at https://pollgab.com/room/brento that require extended answers. Today, I'm hitting just 3 questions:
https://youtu.be/xYZDYuCmqJ8
It's time for a speed round, a rapid-fire tour of your top-voted questions from https://pollgab.com/room/brento:
https://youtu.be/NzO-MN8VJiE
On a beautiful sunny afternoon in the mountains, I went through your top-voted questions from https://pollgab.com/room/brento. Audio is a little rough on this one because I used a new wireless microphone and forgot to put the wind shield on it. If you'd like to watch the spatial video version on an Apple Vision Pro or…
An interesting question came in on PollGab. DBAmusing asked: If a query takes 5-7s to calculate the execution plan (then executes <500ms) if multiple SPIDS all submit that query (different param values) when there's no plan at start, does each SPID calc the execution plan, one after the other after waiting for the prior SPID…
Your challenge for last week was to take this Stack Overflow database query to show the top-ranking users in the most popular location:
[crayon-6a6ece2a8ca11384540524/]
And make it read less pages only by tuning the query? You weren't allowed to make index or server changes, and you weren't allowed to hard code the location in the query since it might change over time.
The Core of the Problem
The main problem is that when we run a statement (like SELECT), SQL Server:
Most of the https://pollgab.com/room/brento questions from this episode had really short and sweet answers. Let's take a break for the holidays and knock 'em out:
https://youtu.be/nhB-dT8_VTg
Y'all were on fire in this one! You posted great questions at https://pollgab.com/room/brento and I worked through 'em:
https://youtu.be/JDTS5KnqewA
On an overcast morning in scenic Camden, Maine, I stood on the docks and took your top-voted questions from https://pollgab.com/room/brento.
https://youtu.be/OFRjC6D7vTs
Sometimes when people post questions at https://pollgab.com/room/brento, the answer is just a link, nothing more, nothing less. It doesn't make sense for me to rehash something that's been covered really well online, and I want to link 'em to the best resource possible. Petr: Huge slowdown of basic queries when using a partitioned table (Partition_Key…
After a long trip through Scandinavia, I'm back in the desert. You posted questions at https://pollgab.com/room/brento and I took the hot seat:
https://youtu.be/guzQGYx3R2M
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…
I got an interesting request for consulting, and I'm going to paraphrase it: We were using Azure SQL DB with automatic index tuning enabled for months. Things were going great, but... we just deployed a new version of our code. Our deployment tool made the database schema match our source control, which... dropped the indexes…
Today, I need your help with some of the top-voted questions from https://pollgab.com/room/brento. Chime in in the comments:
https://youtu.be/RatZKWnDMGI
At https://pollgab.com/room/brento, post the questions you'd like to get my opinion on, and I'll take a break every now and then at the office and go through 'em.
https://youtu.be/YkruJLmhAmU
I start today's Office Hours by playing with the very underwhelming Github Copilot in ADS, then take your questions from https://pollgab.com/room/brento.
https://youtu.be/vOkE8bfdOMU
