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Which Query Used the Most CPU? Implementing Extended Events

SQL Server, T-SQL, Tools
A question that comes up on the forums all the time: Which query used the most CPU. You may see variations on, memory, I/O, or just resources in general. However, people want to know this information, and it's not readily apparent how to get it. While you can look at what's in cache through the DMVs to see the queries there, you don't get any real history and you don't get any detail of when the executions occurred. You can certainly take advantage of the Query Store for this kind of information. However, even that data is aggregated by hour. If you really want a detailed analysis of which query used the most CPU, you need to first set up an Extended Events session and then consume that data. A…
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Containers: More on Volumes

Containers
In my last post I showed how you can create a volume with your container. I then showed a few things you can with a container using a volume. I want to explore volumes just a little bit more. Locate Your Volume To have a little more fun with volumes, first, let's share a drive. You do this in the Settings in Docker Desktop (assuming that's what you're using): While this should just work, it didn't for me until I restarted Docker. So you may need to do that. Go to the drive and create a directory. I'm putting one in at C:\Docker\SQL. Once I've done that, let's create a new container: [crayon-5d079743d2343954238433/] Note, I'm using C:\Docker\SQL in the -v volume command and I'm telling it to map to /sql…
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Containers: Create a Custom Container

Containers
Creating a custom container is where things get truly exciting. There's actually a ton of work and knowledge around this. To start with, I'm going to keep it simple. I'm going to create a container with a database & some data and a couple of general customizations. From that, we'll create our own container. To understand why I've got a series on containers, read here. Setting Up a Custom Container To start with, I'm going to spin up a container with nothing fancy: [crayon-5d079743d283b858692427/] With this running, let's connect up and make some changes: [crayon-5d079743d2844685823750/] With that in place, let's shut down the container and create an image: [crayon-5d079743d284a229576661/] That's it. Now it's time to test it. Consuming a Custom Container Now, it's just a question of treating it like…
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Containers: Working With Volumes

Containers
In the previous two posts on containers I showed how use Docker commands to get an image and create a container. This time, we're going to create a container again, but, we're also going to create a volume so we can do some fun stuff. For an understanding of why I'm doing a series of blog posts on containers, read here. Docker Volumes You can create a container with a volume, or local, persistent storage. The usage is really simple: [crayon-5d079743d5e07587183542/] This will create and kick off a new container based on SQL Server 2017. Nothing to it really. If you get the IP address for the machine, you can connect to it through Azure Data Studio or SQL Server Management Studio. Just be clear, I used a port, 1450,…
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Containers: Creating a Container

Containers
In yesterday's blog post we pulled SQL Server images in preparation for today's blog post where we create containers from those images. If you haven't already, get Docker installed and follow the instructions here to get at least one image on your machine. If you're interested in why I'm talking about containers all week, read this. I'm using all PowerShell commands to control Docker. Docker Run You can use 'docker create' to create an image and then start it up. However, we can just get started running a container from one of the images we downloaded yesterday. We can just simultaneously create and start the container using 'docker run': [crayon-5d079743d6818598752955/] Let's break this down a bit so you know what you just did. The two '-e' statements are setting environment…
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Containers: Getting an Image

Containers
I'm working with Docker running on Windows or Linux. There are other ways to do this, but Docker seems to be a pretty strong standard. I'll leave it to you to get Docker installed on your system. Go here to get the appropriate installation. I explain why I'm learning Docker and containers here if you're interested. Docker Pull The first command you have to learn is 'docker pull'. You then have to supply something for it to pull, an image that will be used to create your containers. I'm using Powershell for the commands I'm posting this week. Here's how you get an image with SQL Server 2017: [crayon-5d079743d70a7854891379/] Assuming you have Docker installed and running, you should get an image downloaded. Depending on your network bandwidth, this could take…
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Learning Containers

DevOps
I find that I'm using containers more and more to get things done with SQL Server. They're so easy to set up for testing, spin 'em up, do stuff, turn 'em off, done. So, as I learn more and more about them, I figured it was time to start to share that learning here on the blog. First up, I'm NOT an expert on this topic. The two best people I know currently on this are Anthony Nocentino and Andrew Pruski. Those are the people you really should be learning the details from. I'm going to try to start to cover the introductory level of containers, Docker, and, at some point in the future, Kubernetes (maybe) and other orchestrators. However, I know that as my knowledge of how to work…
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DevOps Is About Communication

DevOps
I spend a lot of time showing how to use tools to automate database deployments in support of DevOps. However, the one message that I always try to deliver with DevOps is that it's fundamentally not about the tools. No, the single most important thing in DevOps is communication. Therefore, the single most important thing in DevOps is people. People Are Good Are there evil people in the world? Unfortunately, yes. Can even good and decent people do evil? Again, unfortunately, yes. However, most people, most of the time, are trying to do the right thing. I would say that you need to arrive at this position first in order to implement a DevOps solution effectively. You can't be all "Developers are EVIL" or "DBAs are mean" or "My SAN…
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Query Store, Plan Forcing and Table Variables

SQL Server, T-SQL
This weekend I was in Stockholm in Sweden, talking Query Store and plan forcing with Steinar Anderson, when he mentioned the problems he had while forcing plans that had table variables in them. Don't panic. Of course you can force a plan with a table variable, most of the time. Steinar had a fairly focused problem. Before I go on to explain the issue, let me be really clear, Steinar figured out the issue all on his own. When he outlined the problem, I saw immediately what his conclusion was going to be. What's spurring this blog post is that Steinar said he'd searched on the internet and no one had talked about the issue yet. So, let's talk about it. Plan Forcing With Table Variables First up, let's show…
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