How does a live connection impact data transformations in Power BI?

A live connection in Power BI means that the data remains in the source system and Power BI queries it in real-time without importing the data into its data model. This approach has specific implications for data transformations.

When using a live connection, the capability to manipulate data directly within Power BI is significantly restricted. Since the data is not imported but accessed directly from the data source, users cannot perform complex transformations that would typically be done using Power Query. Instead, they can only utilize the measures and calculations defined in the source system or create calculated measures within the Power BI environment based on existing data.

Because of this architecture, no transformations can be applied to the data in Power BI itself, as it doesn’t have a local version of the data to transform. All transformation logic must be defined in the source system or through the data model if that is where the measures are created.

This fundamental understanding of how live connections operate in Power BI underscores why it's crucial for users to prepare and structure their data appropriately in the source system ahead of time, as transformations and data shaping options are not available in the Power BI interface for this type of connection.