Categories: Power BIVaria

STAR SCHEMA ALL THE THINGS

The title says it all, but I’ll explain it anyway. When building a data model that will be used for analysis by human beings, always create a star schemas. Or multiple star schemas connected with conformed dimensions.

Why? Because it’s the most intuitive and user-friendly interface. Because remember, your data model is the user interface to your data. Don’t give your end users a normalized data model (too many joins, complex DAX) or a single flat table (looking at you Tableau. Performance issues, possible complex DAX and scaling issues). Give them a star schema.

You don’t have to take my word for it, but you can watch this awesome video by Patrick of Guy in a Cube where he explains why star schemas are essential in Power BI (and in extent any BI/reporting tool):

He gives a couple of reasons why star schemas are beneficial, and I added one extra in the comments:

If you want more information, definitely check out the book Analyzing Data with Power BI and Power Pivot for Excel by Russo and Ferrari. It dives deeper into the different aspects of why star schemas are preferred for Power BI and gives a lot of DAX examples. It’s a couple of years old, but since it deals with the basics of modelling it is still very relevant.

If you need more background on star schemas – or dimensional modelling – check out the books Star Schema The Complete Reference (one of my favorite technical books of all time) or The Data Warehouse Toolkit: The Definitive Guide to Dimensional Modeling by Kimball.

And remember:


------------------------------------------------
Do you like this blog post? You can thank me by buying me a beer 🙂
Koen Verbeeck

Koen Verbeeck is a Microsoft Business Intelligence consultant at AE, helping clients to get insight in their data. Koen has a comprehensive knowledge of the SQL Server BI stack, with a particular love for Integration Services. He's also a speaker at various conferences.

Recent Posts

Book Review – Microsoft Power BI Performance Best Practices

I was asked to do a review of the book Microsoft Power BI Performance Best…

5 days ago

Create a Numbers Table in Power Query

This is a quick blog post, mainly so I have the code available if I…

1 week ago

Microsoft finally adds Tenant Switcher for Fabric / Power BI

Praise whatever deity you believe in, because it's finally here, a tenant switcher for Microsoft…

1 week ago

Book Review – Humanizing Data Strategy by Tiankai Feng

This book was making its rounds on social media, and the concept seems interesting enough…

2 weeks ago

Free webinar – Tackling the Gaps and Islands Problem with T-SQL Window Functions

I'm hosting a free webinar at MSSQLTips.com at the 19th of December 2024, 6PM UTC.…

3 weeks ago

dataMinds Connect 2024 – Session Materials

The slides and scripts for my session "Tackling the Gaps & Islands Problem with T-SQL…

2 months ago