Category: Self-Promotion

I have a new video:

In this video, I show how we can use the APPLY operator to remove redundancy in the SELECT clause and simplify complex calculations, all with zero performance impact.

This is, as I’ve said in the past, my favorite use case for the APPLY operator. As I’ve become older and (even) more crochety, I’ve sided more and more with “easy to read” versus “runs faster” for code. And when you get “easy to read” with no impact on “runs faster,” I’m all in.

The accounting scenario I show may be a fairly extreme case, but I’d bet that queries similar to this abound in almost any company. A big part of why complex reporting queries are so complex comes from repetition of calculations.

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I have a new video:

In this video, I show how we can use the APPLY operator to find records associated with a “parent” table. We look at getting the latest record, as well as any arbitrary number of records. We also spend time digging into under what circumstances the APPLY operator out-performs other common options.

During the outro segment, I dig into under what circumstances APPLY is the best tool for the job, so stick around for the end.

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I have a new video:

In this video, we will take a look at two KPIs for measuring avidity. We will also show off how to use ranking window functions to order groups of customers.

Click through for the video. There are far too many measures of avidity for me to do a good job explaining them all, and so many of them are closely tied to the specific nature of the business, but hopefully this at least gives you ideas of how the business side may look at user avidity or stickiness.

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I have a new video:

In this video, we will take a look at several useful KPIs for measuring customer growth. We will also demonstrate the utility of DATETRUNC(), calendar tables, and the LAG() and LEAD() window functions.

The calendar table (or date dimension) interlude may seem a little bit weird at first, but I firmly believe that calendar tables absolutely belong on basically every SQL Server instance, even if only in a utility database.

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I continue a series:

In this video, we will dive into three of the most common financial key performance indicators: revenue, cost, and profit. We’ll also take a look at several T-SQL techniques, including aggregation, window functions, and common table expressions.

Click through for the video. This is the first video in the series in which I really dig into specific KPIs and SQL techniques.

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