[Video] Office Hours: Database Q&A
I went live on TikTok and took your top-voted questions from https://pollgab.com/room/brento:
https://www.youtube.com/watch?v=R98zeXqpBRQ
Performance Tuning
Query Exercise: Why Are These 3 Estimates So Wrong?
Our prior Query Exercise introduced SQL Server's 201 buckets problem: its inability to accurately estimate rows for more than 201 outliers in a table. I followed up with a solution using filtered statistics to help with the next 200 outliers, and I talked about how that's really overkill for the simple problem we were facing in that initial challenge.
[Video] Office Hours Q&A: Abrupt Exit Edition
Last week, we had an abrupt intro, and this week, we have an abrupt ending when my camera overheats, hahaha:
https://www.youtube.com/watch?v=pQOk2N3ljCc
T-SQL & Development
Geographic Sharding is Usually a Pretty Bad Idea.
Let's say you built a web app and it became globally popular. You've got users scattered across North America, Europe, and Asia.
In theory, you could shard your data globally: build 3 sets of SQL Servers, one on each continent, and split up their data.
[Video] Office Hours: Abrupt Intro Edition
Today's Office Hours had a ton of technical difficulties because it was my first live stream on both Twitch and TikTok. The first few minutes were cut off, and you can't see the questions onscreen. Nonetheless, there are good answers in here, so let's do it:
https://www.youtube.com/watch?v=Nv0Wnli6kaE
Performance Tuning
Query Exercise Answers: Solving the 201 Buckets Problem
In this week's Query Exercise challenge, I explained SQL Server's 201 buckets problem. SQL Server's statistics only handle up to ~201 outliers, which means that outliers ~202-300 get wildly inaccurate estimates.
In our example, I had an index on Location and perfectly accurate statistics, but even still, this query gets bad estimates because Lithuania is in outliers ~202-300:
About Half Of You Don’t Have Your Databases Under Control.
I ran a poll over on LinkedIn to find out if people have 100% of their databases under some kind of source control or version control.
I broke the answers up into two sets, developers and non-developers, because I had a hunch that the developers' answers would be very different than the rest, and indeed they were:
[Video] Office Hours: Professional Development Q&A
I was supposed to be on a flight to Mexico, but had to cancel at the last minute. While waiting for my favorite bagel shop to open, I went through your professional development questions from https://pollgab.com/room/brento.
https://youtu.be/XeK7sE0Ch98
Performance Tuning
Query Exercise: Solving The 201 Buckets Problem
When you run a query, SQL Server needs to estimate the number of matching rows it'll find - so that it can decide which indexes to use, whether to go parallel, how much memory to grant, and more.
For example, take any Stack Overflow database, and let's say I have an index on Location, and I want to find the top-ranking users in Lithuania:
News & Opinion
Make Money Referring Folks to My Training!
Black Friday is coming.
Every November, we run a big sale on our training & apps. It's a really big deal for us - and for you. I like to think of it as a reward for my long-term readers who can hold out, make plans, and budget to buy at a specific time of year.
[Video] Office Hours: Ask Me Anything About #SQLServer
I took your top-voted questions from https://pollgab.com/room/brento, including a few career-oriented ones:
https://youtu.be/GefrKvKfG1Q
Performance Tuning
Query Exercise Answer: What Makes SELECT TOP 1 or SELECT MAX Different?
This Query Exercise was very different: I didn't ask you to solve a particular problem. I pointed out that I've heard advice that SELECT MAX is faster than SELECT TOP 1, and that's not quite true. I asked you to find factors that would cause these two queries to get different execution plans: [crayon-6ab5edb3888bf553782388/] In the…
SQL ConstantCare® Population Report: Summer 2024 (And Upcoming Gamification Badges)
The short story: SQL Server 2022 finally saw some growth this quarter! Two years after the release, 1 in 10 SQL Servers is finally running the latest version.
The long story: ever wonder how fast people are adopting new versions of SQL Server, or what’s “normal” out there for SQL Server adoption rates? Let’s find out in the summer 2024 version of our SQL ConstantCare® population report.
Production DBA
As a SQL Server DBA, Postgres Backups Surprised Me.
I've worked with Microsoft SQL Server for so long that I just kinda took backups for granted. We run a backup command, and SQL Server: Logs activity to the transaction log while the backup is running Reads the exact contents of the database files, and writes them out to a backup file When it's done,…
[Video] Office Hours with a Special Guest: Count Distinct
I was busy, so I asked a friend to fill in for me and answer your top-voted questions from https://pollgab.com/room/brento. He did a pretty good job:
https://youtu.be/oaRIxcf8sKE
Performance Tuning
Query Exercise: What Makes SELECT TOP 1 or SELECT MAX Different?
These two queries both get the same answer from the Stack Overflow database:
[crayon-6ab5edb388b7e829620500/]
[Video] I Must Be an Idiot: Automatic Tuning Never Works for Me.
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.
[Video] Office Hours in Cabo San Lucas, Mexico
What a comfy morning to sit down with a breakfast margarita and tackle your top-voted questions from https://pollgab.com/room/brento.
https://www.youtube.com/watch?v=E97eDEDLQU8
Thoughts About Stack Overflow’s Annual Developer Survey
Every year, Stack Overflow runs a developer survey about technology, work, community, and more. This year's results include 65,437 responses from developers around the world. The results are biased towards the kinds of developers who use Stack Overflow - 76% of the respondents reported that they have a Stack Overflow account. I would guess that…
[Video] Office Hours in a Mexican Hot Tub
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
