Press "Enter" to skip to content

Author: Kevin Feasel

Creativity, Learning from Code, and the APPLY Operator

Published 2023-07-13 by Kevin Feasel

Rob Farley covers one of my favorite operators:

SQL Server 2005 was released, of course, in 2006, and I had been running the Adelaide SQL Server User Group since September 2005. Information about the new features had been coming through, and I’d been at TechEd Australia 2005 – my first since 1999. I was still an application developer at the time (well, a manager, but still getting my hands dirty), but saw the data as the most important part of my applications. When the T-SQL enhancements in SQL Server 2005 came through, there were two things that caught my eye (I know they were available in Oracle before SQL Server, but I was focusing more on the Microsoft platform by then). They were the OVER clause, and APPLY.

This is all part of a broader story about reading code to learn from it.

Comments closed

Shortcuts and Table Clones in Microsoft Fabric

Published 2023-07-13 by Kevin Feasel

Reitse Eskens takes a shortcut:

A few days ago, I heard the term table clone for the first time, it’s preview release date was to be confirmed and I had no idea what it was about. Two days later, a video emerged where the table clone was explained on a high level. At that point, I started to wonder what the differences are between a table clone and a shortcut. So let’s dig a little into that question!

First I’m going to create a shortcut, then a clone and finally compare the two.

Read on for the comparison, as these are quite different things.

Comments closed

The Five Stages of Code Review Grief

Published 2023-07-13 by Kevin Feasel

Shane O’Neill has an experience:

You have code that keeps coming up as a high consumer of CPU on our systems? OK?

It had gotten to the stage where it kept appearing in sp_WhoIsActive? What’s that? And should it not be “whom is active”? Well, agree to disagree.

Let’s see the code so. Wow, that’s a small scroll bar! Yeah, that’s one of ours.

I should note that “Who is active?” is correct, as the sessions we are inquiring after are the subject of the question rather than the direct or indirect object, and there is no prepositional phrase which would affect the decision.

Comments closed

Object Comparison in R

Published 2023-07-12 by Kevin Feasel

Steven Sanderson checks two objects:

In the realm of programming, R is a widely-used language for statistical computing and data analysis. Within R, there exists a powerful function called identical() that allows programmers to compare objects for exact equality. In this blog post, we will delve into the syntax and usage of the identical() function, providing clear explanations and practical examples along the way.

You can also take a look at the documentation for this function to see a few more examples.

Comments closed

Azure Stream Analytics No-Code Editor

Published 2023-07-12 by Kevin Feasel

Xu Jiang shows off a new designer:

Azure Stream Analytics is a fully managed stream processing engine designed to analyze and process large volumes of streaming data with sub-millisecond latencies. Using a SQL-like query language, it empowers you to analyze your streaming data efficiently. It only takes a few clicks to connect to multiple sources and sinks, creating a Stream Analytics job. 

The no-code editor offers an intuitive user experience that enables you to develop Stream Analytics jobs effortlessly, using drag-and-drop functionality, without having to write any code. It further simplifies Stream Analytics job development experience. With just a few clicks, you can quickly develop jobs to handle diverse scenarios in just minutes. It is available in the Azure Event Hubs portal, and now in Azure Stream Analytics portal as well.

Read on to see what it looks like and what you can do with it.

Comments closed

Understanding String Concatenation with FOR XML PATH

Published 2023-07-12 by Kevin Feasel

Brent Ozar did some noodling:

The first time I saw FOR XML PATH being used to generate a comma-delimited list, I think I stared at it, shook my head to clear the cobwebs, stared at it some more, and then closed the code editor thinking it was complete witchcraft.

And that same thing probably happened the next several times, too.

But eventually, I took a deep breath and read the code more closely to understand what it was doing.

I do like to joke that this is cryptic code that gets handed down from generation to generation, with each generation saying “Don’t touch the code, for you do not understand it.” But as of SQL Server 2017, you don’t need to do this anymore and can use STRING_AGG().

Comments closed

Power BI Projects and Git Review

Published 2023-07-12 by Kevin Feasel

Teo Lachev wants to wait:

But to digress from Fabric, let’s take a look at two developer-oriented and frequently requested features that fortunately doesn’t require Fabric: Power BI Desktop projects and workspace integration with Git. The video in the link is a good starting point to understand how these features work.

Basically, the first feature lets you save a Power BI Desktop file as a *.pbip file which generates a set of folders with human-readable text files, such as the model.bim file (has the model definition described in JSON). Next, you can put these files under source control both in Power BI Desktop using any source-code enabled tool, such as Visual Studio Code or Visual Studio. Currently in preview, Power BI projects is an experimental feature (in fact, the Publish button is disabled so you can’t publish a project to Power BI Service).

Click through for Teo’s thoughts. This is something that I wish had been done 8 years ago, and as Teo points out, there’s still room to grow. But I do consider it a step forward from only being able to save PBIX files.

Comments closed

The Tally Table Splitter

Published 2023-07-12 by Kevin Feasel

Steve Jones talks tally tables:

That being said, years ago I got an article from Jeff Moden on the tally table. I hadn’t used this, and was fascinated. I know Itzik had written about numbers tables early on, but it hadn’t caught my attention. However, in a follow-up, Jeff wrote about a splitter function, which would use the tally table to split strings efficiently. This is the function (credit to Jeff in his article):

Click through for that function. The CLR-based tally table function is still faster, but if you can’t have CLR in your environment, and you split strings so frequently that you need a splitter, and STRING_SPLIT() just doesn’t do it for you (or you’re on an older version of SQL Server), this is a good solution. It’s also the foundation for a principle I have with T-SQL query tuning: sometimes you need to think in terms of pivoted or unpivoted data and operate on it versus the raw data. Here, we’re unpivoting a string into one row per character to get what we need out of it much more efficiently than if we tried to work the string by itself.

Comments closed

Recommended Automatic Indexes and BACPACs

Published 2023-07-12 by Kevin Feasel

Jose Manuel Jurado Diaz shares a note:

During a remote session with a customer, a comparison between the source and target databases revealed a discrepancy in the indexes. Specifically, while the source database contained three types of indexes (PK_xxx, IX_xxx, and NCI_xxx), only the manually created PK_xxx and IX_xxx indexes were visible in the target database after restoration. The absence of NCI_xxx indexes prompted an investigation into the BACPAC export process.

This meant that the BACPAC file didn’t have the set of recommended automatic indexes. Click through for the explanation, though I’m not sure there’s a good way to fix it, short of manually scripting out those automated indexes yourself.

Comments closed

T-SQL Query Transformations and Performance

Published 2023-07-12 by Kevin Feasel

Erik Darling isn’t satisfied with “good enough”:

Query tuning is hard work, especially when queries run for a long time and you have to test various changes trying to get it down to a reasonable runtime.

There are, of course, things you pick up intuitively over time, and figuring out where problems in actual execution plans has gotten easier with operator runtimes.

Beyond basic query tuning intuition comes the really creative stuff. The stuff you’re amazed anyone ever thought of.

Click through for two really interesting examples.

Comments closed