Difference between Import, DirectQuery, and Live Connection Modes in Power BI

Import Mode:

In Import mode, data is copied from the data source into the Power BI model. The data is stored locally (or in Power BI cloud storage when you publish the report) and refreshed on a scheduled basis. Import mode is ideal for performing complex data transformations and analysis, as the data is fully loaded into Power BI, allowing for faster performance in reports.

Power BI owns both Data and Model in Import mode.

DirectQuery Mode:

In DirectQuery mode, data is not stored in the Power BI model. Instead, every time you interact with a report, data is queried directly from the source. This ensures the data is always up-to-date, but it can put additional load on the data source, particularly if there are many users. DirectQuery mode is best for real-time data access, especially for large datasets that need frequent updates.

Power BI owns only the model in DirectQuery mode.

Live Connection Mode:

Live mode operates similarly to DirectQuery but is supported only for specific data sources like Power BI datasets or Analysis Services. In Live mode, data is stored in the source model and is retrieved directly from the data source whenever the model is opened, ensuring the data is always current. This mode allows you to rely on the existing data without needing to access the report directly. However, it can also place a significant load on the data source, especially with a high number of users.

In Live connection mode, both Data and Model belong to the source.