06Jan 2020 by Grant Fritchey 8 Comments

Execution Plans: First Operator

SQL Server, T-SQL
The first time you see a new execution plan that you're examining to fix a performance problem, something broken, whatever, you should always start by looking at the first operator. First Operator The first operator is easily discerned (with an exception). It's the very first thing you see in a graphical execution plan, at the top, on the left. It says SELECT in this case: This is regardless of how you capture the execution plan (with an exception). Whether you're looking at an execution plan from the plan cache, Query Store, or through SSMS, the execution plan, regardless of complexity, has this first operator. In this case, it says UPDATE: If you get an execution plan plus runtime metrics (previously referred to as an "actual" execution plan), you'll still see…
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09Dec 2019 by Grant Fritchey 24 Comments

Distributing Jupyter Notebooks

Professional Development, SQL Server
If you're working with the Microsoft Data Platform, you should be, at the least, exploring Azure Data Studio as a new tool in your toolbox. One of the big reasons for this is the inclusion of Jupyter Notebooks. For those who don't know, Jupyter Notebooks are an open source documentation tool that lets you combine text and pictures with live code. From this we can talk about runbooks that you can share with people, lessons in combination with videos, presentations, interactive software documentation and lots more. I'm myopically focused at the moment on Azure Data Studio, but there are a lot of other places and ways to create or consume notebooks. However, I'm going to keep my focus. The issue I'm running into, is distributing the notebooks. Where to go…
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25Nov 2019 by Grant Fritchey 4 Comments

Containers: Upgrading SQL Server from 2017 to 2019 RTM

Containers
Throughout the pre-release of SQL Server 2019, I was demoing an effectively instant, and magical, container upgrade from 2017 to 2019. However, when I finally downloaded the release bits in a new image, the magic went away. In fact, I got errors, so what happened? Non-root User In SQL Server 2017, the containers were running as root. The thing is, you're basically setting up your instance to run as administrator of the system. We all know that's a no-no. So, in SQL Server 2019, Microsoft fixed this and now the SQL Server instance within the Linux container runs as mssql, much better. However, this immediately causes issues when we're doing an in-place upgrade using a volume on a 2017 container to move to 2019. We're not root any more. Let's…
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19Nov 2019 by Grant Fritchey No Comments

Your First Jupyter Notebook

Tools
In April, I said I was going to start learning Jupyter Notebooks. It's November. Let's get going with your first Jupyter Notebook. A quick aside before we start. I think one of the huge strengths that is going to come out of these things is as a runbook. You can share a notebook with someone, they can run the queries on it against their own systems and return the book, with the results to you. That's going to be extremely useful as a troubleshooting tool, but has all sorts of other functionality as well. I strongly suggest you start learning these things, as I am. Azure Data Studio There are a number of ways to create and consume Jupyter Notebooks, but I want to focus on the functionality around data…
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11Nov 2019 by Grant Fritchey 4 Comments

Docker, Git and DBATools

DevOps, Professional Development
For those who don't know, last week was the PASS Summit. It's an amazing event every year, but this last week, I saw a ton of indications that our peers are spotting the changing technology landscape largely defined by three tools, Docker, Git and DBATools. None of those indications resonated quite as much as this tweet from Kevin Hill: 3 things I can no longer justify ignoring: #dbatools Git and #Docker for my dev SQL work@cl @sqldbawithbeard @Kendra_Little and @unclebiguns @GFritchey, I blame you 🤪😂There’s more but those are top 3— SQL Cyclist (@Kevin3NF) November 9, 2019 There are a million things to learn about in our rapidly shifting technological landscape, but I think this assessment, especially the way it was put, "no longer justify ignoring" really nails some of…
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22Oct 2019 by Grant Fritchey 2 Comments

Every Execution Plan Is An Estimated Plan

SQL Server
I consider myself to be the most responsible for making such a huge deal about the differences between what is labeled as an Estimated Plan and an Actual Plan. I walked it back in the second edition of the Execution Plans book. Hugo and I completely debunked the issue in the third edition of the Execution Plans book. That is the one you should all be referencing now. As I like to joke, the guy who wrote the first two editions of the book was an idiot (and lest anyone take offense, let's be clear, I'm the idiot). Now, I'm trying my best to make this whole issue more clear. Let's talk about the "different" plans you can capture in SQL Server. Estimated Plan This is where you have a…
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14Oct 2019 by Grant Fritchey 1 Comment

Database Fundamentals #23: Filtering Data

Database Fundamentals, SQL Server
If you've been reading these Database Fundamentals posts, you've already seen the WHERE clause because of your use of it when manipulating data with DELETE and UPDATE statements. It's also been used several times earlier in this series to limit the values returned from a SELECT statement. The primary places where people run into trouble with T-SQL is in the JOIN criteria and the WHERE clause criteria. This occurs because they don’t understand well enough what the filters and operators they’re using will do. They end up returning too much data because they didn’t us the WHERE clause or misapplied it. They also filter too much data out. Just remember, there are even more functions than we go over here in this series. While these basic operators answer most needs,…
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07Oct 2019 by Grant Fritchey 5 Comments

SQL Injection Mitigation in SQL Server 2019

SQL Server
I've been teaching a lot more about SQL Injection lately (including blog posts). I've been doing this because, despite this being a 21 year-old problem with well defined solutions, we're still dealing with it. Recently, while sitting in the speaker room at Techorama Netherlands (fantastic event, strongly recommended), I had the opportunity to spend a little time with Niko Neugebauer. I was freaking out because my demos were failing (fixed 'em finally). Niko was talking to me about the new Feature Restrictions and their effect on SQL Injection in SQL Server 2019. I didn't know what he was talking about, so I had to look it up. Of course, top resource, Niko's blog. Feature Restrictions in SQL Server 2019 The Feature Restrictions in SQL Server 2019 are actually being added…
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23Sep 2019 by Grant Fritchey 8 Comments

Database Fundamentals #22: Using the Join Operator, CROSS JOIN

Database Fundamentals
While the CROSS JOIN is not used much, and, depending on the size of your data it can be dangerous, there are some uses for it. For example, you may want to write a query that will summarize all the sales for the companies and people in your system. You can do this using what is called an aggregate operation or a GROUP BY: SELECT c.CompanyName, p.LastName, SUM(ft.TransactionAmount) AS 'TransactionTotals' FROM Management.Company AS c JOIN Finance.FinancialTransaction AS ft ON c.CompanyID = ft.CompanyID JOIN Personnel.Person AS p ON p.PersonID = ft.PersonID GROUP BY c.CompanyName, p.LastName; This will add all the values up in the SUM operation for each company and each person that has values so that your data will look like this: The only problem with this is, you can’t…
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19Aug 2019 by Grant Fritchey 1 Comment

How Do You Make DevOps Succeed?

DevOps
I love going to SQLSaturday events because I'm always asked questions that make me think. I was just at SQLSaturday Indianapolis (a great event, if you weren't there, you missed out). I was giving a session called "Extending DevOps to SQL Server" (which I'm giving this Saturday at SQLSaturday Providence). I was talking about the fact that I've been involved in successful DevOps implementations and I've been involved in failed DevOps implementations. The question that came up was, "What were the key differences between the failed and successful organizations?" Great Question. Management Buy-In I've seen attempts to implement DevOps strictly from the IT side of things. A relatively high functioning team recognizes the benefits an agile approach that's oriented towards improved collaboration between people that uses automation in support of…
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