Summary: This Power BI Basics Series takes you through the steps of an end to end Power BI process and which personnel should be involved at which stage.    The purpose of this series is to provide a quick overview so you can direct resources and plan the introduction of Power BI to your company.  This is Part 3:  Power BI Data Modelling.
Article Type: How To (September 2018)
Related Product(s): This article relates to the following products:

  • Power BI
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Power BI Basics: Getting Started with Power BI

There are many “How To” videos on Power BI but sometimes a quick overview of an end to end process can be helpful at the outset.  Once the outline of the whole process has been understood (without detail at every stage) it is then possible to plan how your business should approach Power BI and which personnel should be involved at which stage.  The purpose of this  series is to provide that quick overview so you can direct resources and plan the introduction of Power BI to your company.  This article (Part 3) covers Power BI Basics: Data Modelling.

This Power BI Basics series covers the following topics:

  1. wer BI tools & Licensing overview
  2. Importing and Transforming data
  3. Power BI Data Modelling
  4. Creating Visualizations
  5. Publish Docs to Power BI Service

Power BI Data Modelling

As mentioned in the previous section (Importing and Transforming Data) some manipulation of the data occurs after it has been imported.  The purposes of data manipulation at this later stage are:

  • Ensure that tables relationships are correct
  • Add new fields required for the visualisations.

Table Relationships

The first example of Power BI data modelling is the ability to establish links between the imported tables.  By clicking on the Relationship icon on left hand side the view of the loaded tables and any existing links between them are shown.

Power BI Data Modelling 

To add a new link simply select a field in one table and drag the mouse over to a field in a second table.  At that point a pane appears where details of the link can be set.

Power BI Data Modelling Screenshot

Adding Fields/Calculations

The second example of modelling is to add new detail to the existing tables.  It is possible to add:

  • Column
  • Measure

Column

This will add a value to the table for each row.  The example below adds a column to identify each Location as being local or international.

Power BI Basics: Data Modelling

Power BI Modelling Data Screen

The syntax used for the calculating column and/or measure values is DAX.  Details of the DAX code can be found here.

Measure

This will add an expression which will return values when added to a visualisation.  The example below calculates the volume of sales where the date is between 1st Jan and current date of this year.

Power BI Data Modelling Syntax

Power BI Data Modelling Column

Below are two examples of the fields above being utilised within visualisations.

Power BI Data Modelling Visualisations


Read the next article (Part 4)  in this Power BI Basics series: Creating Visualisations.