Determining the Cost Threshold for Parallelism

SQL Server, SQL Server 2016
In the previous post, I showed how you can get full listings of your execution plan costs. Knowing what the values you're dealing with for the estimated costs on your execution plans can help you determine what the Cost Threshold on your system should be. However, we don't want to just take the average and use that. You need to understand the data you're looking at. Let's explore this just a little using R. Mean, Median, Range and Standard Deviation I've used the queries in the previous blog post to generate a full listing of costs for my plans. With that, I can start to query the information. Here's how I could use R to begin to explore the data: library("RODBC", lib.loc="~/R/win-library/3.2") query <- "SELECT * FROM dbo.QueryCost;" dbhandle <-…
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Learning R: Happy With My Book Choice

Data Science
This is just a quick update. I wrote about the two books I'm using to learn R. Well, I'm extremely happy with my choices, especially with the Using R for Introductory Statistics book. It has problems at the end of each chapter. No, unlike our elementary school math books the answers are not in the back of the book (you knew that, right?). The answers are however very clearly within the text of each chapter. I've really been enjoying these little problems. They're helping me cement both my understanding of R and my understanding of the mathematics. I strongly recommend this book.
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Learning R: Hitting the Books

Data Science
I've been using a series of web sites while I was starting the process of learning R. I've highlighted several of these in previous posts. While people will claim to learn better based on a single source-type, studies have found that you actually learn best by a multitude of methods. So, in addition to video instruction, web sites, guides, etc., I'm also going to read a few books to help learn R. After a lot of research, I've arrived at two that I'm starting with. The first is R In Action. I'm already on the 2nd chapter and I'm enjoying the style and approach. The other book is Using R for Introductory Statistics. I'm using this book because as I have already picked up, the real trick to learning R…
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Learning R: Hard Lessons

Data Science
I've always found the best way to learn a new programming language is to start building stuff, solving problems, using the language. Even if you do things badly or inefficiently, you're figuring out how to put the language to use. I tried the same thing with R. Fair warning, there is no happy conclusion to this story. It's a lesson about learning, not about solving a problem. After poking at the R language for a little while, I decided I was ready to solve a problem. I have a fantastic idea for demonstrating the usefulness of the language specifically for DBAs. I won't go into what it is here because I'm still hoping to solve this problem and it will provide a fantastic blog post. Anyway, I have a very…
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Learning R: Foundations

Azure, DevOps, Professional Development, SQL Server 2016
Learning a programming language is largely an act of using that language to do stuff. Done. However, the big thing about R is the mathematical and statistical analyses that can be easily run against your data sets. This means, part of learning this language is learning another, that of data science. I'll be posting about how I'm learning R, but I also should tell you how I'm picking up on Data Science. First and foremost, madman he may be, but one of the few sources of information that I simply trust is Buck Woody. He's been running a series on Data Science. Here's an excellent example on how to pick a particular algorithm. These are must reads. Next, I'm starting a book called Data Science for Business: What you need to…
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Changing Course On Learning

Azure, Database Lifecycle Management, DevOps, DocumentDB, Professional Development
With all the new stuff on the Microsoft Data Platform, it's really hard to keep up with it all. I had announced my plans to charge down the DocumentDB road to try to get the basics of that in my head along with learning some JSON so I could get what all the hoopla is about. However, after a lot of thought and some extensive meetings at Redgate, I'm looking to shift my learning in a new direction. First up. Arrrrrrrrr! No, it's not yet "Talk Like a Pirate Day." I'm going to start learning the R language. It's a language for statistical computing and is one of the many underpinnings for what's going to be happening with a lot of the Machine Learning capabilities in the Data Platform. With Azure…
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