Max Degrees of Parallelism (MAXDOP) tells the database engine, "If you decide to parallelize a query, go parallel with this many worker threads."
(It's a little more complex than that - there is also a coordinating thread, plus a single plan might have multiple parallel zones that each consume MAXDOP worker threads, but for the sake of this blog post, let's keep it simple.)
I've been pretty vocal here on the blog and on social media about the reliability problems with Microsoft Fabric. Today, I've got good news: Microsoft released a new Fabric status page and a known issues page, something that really does take guts given the current reliability situation. The status page still appears to be manually updated, not automated, but at least it acknowledges outages like how SQL endpoints are currently returning incorrect query results:
Update 2025/07/21: Microsoft heard the complaints, and fixed the reliability added a better status page. Baby steps.
Last week, Microsoft Fabric went down yet again for hours on multiple continents.
tl;dr: if you use Azure SQL DB Hyperscale's auto-scaling, it's probably not cutting your bill down because like SQL Server, Hyperscale doesn't automatically relinquish memory, and it'll be up to you to manually manage your own memory if you wanna cut your bill.
Now for the long story.
Or perhaps another way to phrase that is, Microsoft is up to something with parallelism. I don't know how long it's been this way - could even be since the launch of Azure SQL DB Serverless - but I just now noticed it while helping a client with a slow query. When you view an…
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…
On August 30, Azure's Australia East data center had a big problem, affecting customers like Bank of Queensland and Jetstar. Here's the timeline: 30 August 2023 @ 08:41 – Voltage sag occurred on utility power line 30 August 2023 @ 08:43 – Five chillers failed to restart 30 August 2023 @ 10:30 – Storage and SQL…
To celebrate this month's launch of our new class, Fundamentals of Azure Networking for the Data Professional, we're making one video a day completely free. Here's what's on tap this week:
July 24: Demo: Working With a VPN
July 25: Hub and Spoke vs Mesh Design Patterns
July 26: Microsoft-Managed Virtual Networks
July 27: Demo: Azure Data Factory Networking
July 28: Recap and Resources
To celebrate this month's launch of our new class, Fundamentals of Azure Networking for the Data Professional, we're making one video a day completely free. Here's what's on tap this week:
July 17: Demo: Using Virtual Networks for Data Services
July 18: Demo: Private Networks Without Public Access
July 19: Demo: Multiple Private Networks
July 20: Demo: Network Security Groups
July 21: Extending Networks to Azure with VPNs
Raise your hand if you've ever blamed the network.
You're responsible for the health, security, and uptime of your company's data services in Azure. You've provisioned a few services, but every now and then, you run into problems making your services reachable and reliable from different users and app servers.
SQL Server Always On Availability Groups help you build a more highly available database server by spanning your database across two or more SQL Server instances. When the primary goes down, the secondary can take over. You can also scale out reads to the secondary servers. Distributed Availability Groups take this a step further and…
Let's get you some answers.
Is Azure SQL DB PaaS, IaaS, or SaaS?
Azure SQL DB is platform-as-a-service (PaaS). Microsoft manages most common database tasks for you, and they act as your DBA.
This also means that like a DBA, Microsoft will tell you "no" if you try to implement something that they don't support. There's no negotiations: the answer is just no.
Who is Azure SQL DB for?
Azure SQL DB is a good fit for new applications.
You manage database servers for your company, and they're thinking about migrating everything to Microsoft Azure. You've searched the web for information and advice, but everything you're finding is outdated.
You just want a list of things to review on your servers, an overview of what won't work in the cloud, and how to pick alternatives or workarounds.
You manage servers, not invoices. Your company has started to move their databases into Azure, and they're asking questions that you're just not ready to answer. How big does your server need to be when you're moving an existing database up to the cloud? How are servers measured? How do you measure to know if your new Azure SQL DB is overwhelmed, or if it's a code or index problem? How do you make the right adjustments once you're up there?
Folks often email me and ask, "Brent, why don't you do training classes on Azure?" The answer is simple: the products change faster than I can recoup the cost of building the training material. By the time the class gets enough revenue to pay off the downtime for building an Azure (or AWS or Google) training class, the material's out of date. I'm sure you've sat through an online video where you've noticed things that are already no longer true.
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 Thallam Kodandaramaih, Hanuma Kodavalla, Prashanth Purnananda, Adrian-Leonard Radu, Chaitanya Sreenivas Ravella, and Girish Mittur Venkataramanappa (2019).
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…
Many of us DBAs have been able to put off dealing with the cloud. That time is quickly coming to an end. But when was resistance to change ever a great career strategy in a tech field? Besides, two or three or four years from now, you might not have much choice in the matter. You don't want to be way ahead of the curve, but you do wanna be just ahead enough, and so the time to start your cloud education is now.
If you've got a database that doesn't need to be on all the time, Azure SQL DB Serverless is in public preview now. It makes a lot of sense for those development databases you have to keep around, but don't really want to pay for.
If your database doesn't get any queries for 6 hours, it'll pause billing, and automatically resume again when your queries kick in. Here's how to set it up in the portal:
No no, April Fool's was yesterday.
Hear me out.
