Press "Enter" to skip to content

Author: Kevin Feasel

Star Schemas and Keys

Published 2025-10-27 by Kevin Feasel

Chris Barber provides a primer on the types of keys that are critical for a star schema:

Keys are a core component of star schema modelling; relationships between tables are built using the keys. This article covers:

  1. The main key types
  2. Star Schema diagrams
  3. Best practices when using Keys

An understanding of keys become increasingly important with more complex solutions. Not only do you need to understand them from a modelling perspective, but a common vernacular is required to communicate with team members.

It’s easier to think of the keys Chris describes in two separate classes rather than four unique items. Surrogate and natural keys are descriptors of a primary key (or any other unique/alternate key), after all.

Leave a Comment

Decimal Precision and Rounding in SQL Server

Published 2025-10-27 by Kevin Feasel

Jiri D. provides a warning:

Do you ever worry about how you declare NUMERIC or DECIMAL data types in SQL?
Do you sometimes “add a bit more” precision—just to be safe?
Have you considered how that small decision could actually change your arithmetic results?

I ran into this recently when comparing data between two environments that should have produced identical results. One calculated field was slightly off — and the culprit turned out to be a difference in numeric data type declarations.

Read on to see what happened. The differences weren’t massive, but if you were expecting an exact match, seeing a difference, even at the 7th or 8th spot after the decimal, could be jarring.

Leave a Comment

Installing SQL Server 2025 Standard Developer Edition on Linux

Published 2025-10-27 by Kevin Feasel

Rajendra Gupta tries out a new edition available in SQL Server 2025:

In the article “Install SQL Server 2025 Standard Developer Edition,” we explored the installation of SQL Server 2025 Standard Developer Edition on the Windows platform. SQL Server 2025 (Preview) also works on Linux editions, and it is equally important to cover the installation steps. Let’s see how we can install it on an AWS EC2 instance running Ubuntu.

The first half of the article covers spinning up an EC2 instance. Interestingly, the prompt to choose your edition of SQL Server was only partially updated—it still asks for you to choose an option between 1 and 10, but there are now 11 options available and I’m now curious if the conditional logic in the script to choose your edition works if you want to use Enterprise Core. Rajendra does note an error message that pops up around licensing, but that could be a release candidate thing.

Leave a Comment

Adding Commas to Numeric Output in SQL Server

Published 2025-10-27 by Kevin Feasel

Andy Yun is speaking my language:

One thing that’s always driven me crazy is when I have large numbers in my resultsets and the lack of commas for readability. For a lot of different things I do, the more commas a number has, the more attention I want to give to a given value.

Andy shows examples of formatting to two and zero spots after the decimal, respectively. In a talk I give on analyzing business data with T-SQL, I also demonstrate how to show currency-based results:

FORMAT(SUM(o.Quantity * sih.LastCostPrice), N'$0,###.##') AS TotalCost

This starts each cost record with a dollar sign, ensures you have commas in the thousands spots, and have a two-digit decimal value. That would return back a result like $31,409,113.00, which is a lot easier to read than 31409113.

Leave a Comment

Linux and NUMA

Published 2025-10-27 by Kevin Feasel

Chris Travers provides an overview of NUMA:

This entry in the series focuses on the low-level hows and whys of Non-Uniform Memory Access so that it is possible to understand the solutions and recommendations later with a focus on conceptual details.  Unfortunately in many details this requires focusing on technical details as often the concepts without the details are confusing at best.

Read on for a quick history of NUMA and what options are available in the Linux kernel.

Leave a Comment

OneLake Security and the Fabric SQL Analytics Endpoint

Published 2025-10-24 by Kevin Feasel

Freddy Santos takes us through the latest with respect to security in OneLake:

OneLake Security centralizes fine-grained data access for Microsoft Fabric data items and enforces it consistently across engines.
Currently in Preview and opt-in per item, it lets you define roles over tables or folders and optionally add Row-Level Security (RLS) and Column-Level Security (CLS) policies. These definitions govern what users can see across Fabric experiences.

Read on to see what you can do.

Leave a Comment

Custom Calendars in Power BI

Published 2025-10-24 by Kevin Feasel

Kenneth Omorodion needs a calendar dimension:

Before September 2025, there was a complex workaround to create time intelligence calculations in DAX catered to different calendar types apart from the standard Gregorian calendar. With the Power BI September 2025 feature updates (still in preview at the time of writing), it is now readily possible to define custom Power BI custom calendars based time intelligence, like Shifted Gregorian, ISO, and retail calendars, in the data model and then use the new extended DAX functions against these calendars.

The new feature eliminates the need for complex workarounds and ensures cleaner and more accurate reporting for organizations. This tip will explain the different calendars used in time intelligence reporting and how to define them based on the new calendar-based time intelligence capability in Power BI.

Read on for several examples of how this works.

Leave a Comment

PostGIS Tuning via pg_stat_statements

Published 2025-10-24 by Kevin Feasel

Paul Ramsey wants to make spatial querying faster:

A reasonable question to ask, if you are managing a system with variable performance is: “what queries on my system are running slowly?”

Fortunately, PostgreSQL includes an extension called “pg_stat_statements” that tracks query performance over time and maintains a list of high cost queries.

This particular post is more about pg_stat_statements in general rather than specific advice for PostGIS, but it does lay out some recommendations for using pg_stat_statements in spatial-heavy environments.

Leave a Comment

Microsoft Fabric Direct Lake Join Index Creation

Published 2025-10-24 by Kevin Feasel

Phil Seamark explains a recent change:

If you’ve been working with Direct Lake in Microsoft Fabric, you’ll know its magic resides in its ability to quickly load data. It loads data into semantic models from OneLake when needed. This feature eliminates the overhead of importing. But until recently, the first query on a cold cache might feel sluggish. Why? One reason for this is that Direct Lake must build a join index. This index is added to the model during the first query. This index is a critical structure that maps relationships between tables for efficient lookups.

Earlier, this process was single-threaded and slow, especially on large tables with high cardinality. The good news? That’s changed.

Read on to see how, what a join index is, and what this impact looks like in practice.

Leave a Comment

Learning Microsoft Fabric Real-Time Intelligence

Published 2025-10-24 by Kevin Feasel

Valerie Junk picks up a new skill:

If you are reading this article on my website, chances are you know me from my Power BI content, the videos, articles, tutorials, or downloads, or you came across it on LinkedIn. I want to be upfront: I am a front-end/business person. I create reports that lead to action and help businesses make smarter decisions while building a data-driven strategy.

When I started talking about Fabric Real-Time Intelligence, people were surprised. Some were curious. Others probably wondered what had happened. For me, real-time reports push you to approach design in a completely different way because users need to take action immediately. Decisions happen in the moment, and that changes everything about how you visualize and structure information, so that got me interested!

Read on to see how Valerie picked up KQL as a language, as well as some of the challenges involved. I will say, the Eventhouse is also the fastest mechanism Microsoft has to query large amounts of data in Microsoft Fabric—it beats out the lakehouse and warehouse pretty handily.

Leave a Comment