16Apr 2018 by Grant Fritchey 4 Comments

Execution Plan Shortcoming in Extended Events

SQL Server, SQL Server 2016, SQL Server 2017
I use Extended Events almost exclusively for capturing query metrics. They are the most consistent and lowest cost mechanism for getting the time and resources used by a query. They can be filtered, combined with other events, they're just marvelous... until you capture an execution plan. Execution Plans in Extended Events Don't get me wrong. Capturing execution plans with Extended Events is the way to go if you're attempting to automate the process of capturing plans on specific queries on an active system. It's step two that bugs me. So, we capture the plan. Here's an example script. Captures all the various plans and the batch, puts 'em together using causality tracking: CREATE EVENT SESSION ExecutionPlansOnAdventureWorks2014 ON SERVER ADD EVENT sqlserver.query_post_compilation_showplan (WHERE ( sqlserver.database_name = N'AdventureWorks2014')), ADD EVENT sqlserver.query_post_execution_showplan (WHERE…
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11Apr 2018 by Grant Fritchey No Comments

Privacy and Protection, By Design

Redgate Software
With all the noise about the upcoming enforcement of GDPR, I know that people are starting to focus more on privacy and protection. Add in all the other news about data breaches and data leaks and suddenly, privacy and protection isn't just a business concern, it's personal. Where do you go if you want to learn more? How about the SQL Privacy Summit? SQL Privacy Summit Redgate is hosting the first SQL Privacy Summit on May 18th in London, brought to you by the producers of SQL in the City. Yes, lots of information on the GDPR and compliance will be available. However, we're going way beyond that. The reason it's called the Privacy Summit and not just "The GDPR Summit" is because we're talking about more than compliance. We…
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09Apr 2018 by Grant Fritchey 25 Comments

GDPR, Database Backups, and the Right to be Forgotten

DevOps
I've said it before, but it bears repeating, there is no cause for any kind of panic when it comes to the GDPR. None. There are however, a number of concerns. One of those concerns is, well, concerning. How does the right to be forgotten within the GDPR impact database backups? Let's discuss what we know. The Right To Erasure Each of the articles within the GDPR lays out a topic. Article 17 is pretty darned clear about the topic: Right to erasure ('right to be forgotten') Basically, the individuals, also known as the data subject, also known as natural persons, in short, people, can request that you remove their data from your system. The first sentence lays out the gist of the idea quite well: The data subject shall…
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02Apr 2018 by Grant Fritchey 4 Comments

Buggy Whips 2.0

DevOps, Professional Development
I recently found myself rereading a very old blog post of mine, from the very beginning of this blog, discussing Buggy Whips. I'll save you the long read, I was learning new tech, it made me second guess my working assumptions, I was curious if I was manufacturing a buggy whip while watching an automobile drive by. 2008 to 2018 Well, I'm still here. In fact, Feature Driven Development has disappeared from the lexicon and the project that it was introduced to took years longer than anticipated, performed horribly, and had to have a major redesign and rework to be fundamentally functional (all after I left the old organization). So, my fears that database design was a thing of the past were just that, fears... right? Yes and no. Here…
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30Mar 2018 by Grant Fritchey 4 Comments

YouTube Channel Update: March 30, 2018

Professional Development
Hey everyone! Here's the latest stuff on my new YouTube Channel. Please let me know if these videos are helpful. Also, if you have requests for videos on a particular topic, even a video of a blog post I did here, let me know. I take requests and I'm more than happy to help. I've been talking a lot about the GDPR. I released three videos on this topic this week alone: [embedyt] https://www.youtube.com/watch?v=FSbrhv1Fuh4[/embedyt] [embedyt] https://www.youtube.com/watch?v=YFyS45kvtMY[/embedyt] [embedyt] https://www.youtube.com/watch?v=YLYxflj8O9A[/embedyt] I also released a video on using SQL Prompt to help your team audit their code: [embedyt] https://www.youtube.com/watch?v=4TBHGuhgS4E[/embedyt] Finally, I added a video discussing database mirroring as it relates to Azure SQL Database [embedyt] https://www.youtube.com/watch?v=I26K-FWilXA[/embedyt]
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26Mar 2018 by Grant Fritchey 6 Comments

Query Store and Automated Cleanup

SQL Server 2016, SQL Server 2017
Query Store has mechanisms for automatically cleaning your data. It is possible to cause them to break down. While presenting a session about the Query Store recently, I was asked what happened if you set the size of the Query Store below the amount of data currently in the store. I didn't know the answer, so we tried it. Things got a little weird. Bryan Hundley of Marathon Consulting asked the question, so Bryan, this blog post is for you. Automated Cleanup There are actually two kinds of automated cleanup inside the Query Store. First, you have a time-based cleanup. By default it keeps queries that have been accessed within the last 30 days. Anything older, it tosses. If you have the stale_query_threshold_days (all in sys.database_query_store_options) set to 0, it…
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19Mar 2018 by Grant Fritchey 1 Comment

Query Monitoring and the GDPR

DevOps
I've been reading the General Data Protection Regulation (GDPR) and discussing the ramifications of the beginning of enforcement with lots of people. The implications of it all are fascinating. The real serious issues remain primarily a business problem, with business defined solutions. However, there are technology issues that we need to think about. For example, performance metrics are going to be impacted by the GDPR. Private Data and Monitoring Queries First and foremost, let me say something I've said before. The vast majority of the focus around GDPR has to come from your business. Second, the bulk of your work and focus must be on ensuring core functionality in support of the GDPR. Third, the attack vectors and leaks for GDPR are not going to primarily be around something like…
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12Mar 2018 by Grant Fritchey 6 Comments

Execution Plans and the GDPR

SQL Server, SQL Server 2016, SQL Server 2017
What? Execution plans and the GDPR? Is this it? Have I completely lost it? Well, no, not on this topic, keep reading so I can defend myself. GDPR and Protected Data The core of the GDPR is to ensure the privacy and protection of a "natural person's" information. As such, the GDPR defines what personal data is and what processing means (along with a bunch of additional information). It all comes down to personally identifying (PI) data, how you store it, and how you process it. More importantly, it's about the right for the individual, the natural person, to control their information, up to and including the right to be forgotten by your system. OK. Fine. And execution plans? Execution Plans and PI Data If you look at an execution…
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05Mar 2018 by Grant Fritchey 11 Comments

Every Single Execution Plan is an Estimated Plan

SQL Server, SQL Server 2016, SQL Server 2017
All the execution plans are estimated plans. All of them. There fundamentally isn't any such thing as an "Actual" plan. Where Do You Get Execution Plans? There are a lot of sources for execution plans. You can capture them using extended events (or, if you must, trace). You can capture them through the Management Studio gui. You can also capture them from the SQL Operations Studio gui. You can query the cache through the DMVs and pull them in that way. You can look at plans in query store. All these resources, yet, for any given query, all the plans will be identical (assuming no recompile at work). Why? Because they're all the same plan. Each and every one of them is an estimated plan. Only an estimated plan. This…
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02Mar 2018 by Grant Fritchey No Comments

YouTube Channel Update

Misc
Hey! Here's the latest on my YouTube Channel. Click on through and subscribe. I'll be doing lots of stuff on the Microsoft Data Platform, GDPR, DevOps, Redgate, and all sorts of IT related information. Here are the last couple of weeks worth of videos: Very popular was my discussion of the idea that the reason DBAs don't adopt the latest and greatest piece of shiny is because we're all beholden to vendors instead of trying to make good decisions for our the organizations that pay us (as if the "best" decision is to always grab the new shiny). OK, I'm giving away my thoughts, here's the video: [embedyt] https://www.youtube.com/watch?v=0TVeRSc3gLg[/embedyt] Next most popular was my question, so, if we're not resisting change because of vendor lock (and we're not) why are…
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