Transforming and cleansing source data

The applied within Power BI's M queries serve to protect the integrity of the data model and to support enhanced analysis and visualization. The specific to implement varies based on data quality, integration needs, and the goals of the overall solution. However, at a minimum, developers should look to protect the integrity of the model's relationships and to simplify the user experience via denormalization and standardization.

This recipe includes examples of protecting a data model from duplicate values and enhancing the quality of a dimension column via a relationship to a separate data source.

Getting ready

To best follow the duplicate removal example, you may identify any data models that source directly from an unstructured source such as an Excel or text file.

How to do it...

Remove duplicates

The objective of this is to prevent refresh failures due to duplicate source values in the relationship column of a dimension table. Additionally, the duplicates...