Historical data analysis

Hi kmas

For the streaming dataset which has the 'Historical Data Analysis'  option disabled, Power BI only stores the data into a temporary cache, which quickly expires.

There is no underlying database, so you cannot build report visuals using the data that flows in from the stream. As such, you cannot make use of report functionality such as filtering, custom visuals, and other report functions.

When Historic data analysis is enabled, the dataset created becomes both a streaming dataset and a push dataset.

With a push dataset, data is pushed into the Power BI service. When the dataset is created, the Power BI service automatically creates a new database in the service to store the data. Since there is an underlying database that continues to store the data as it comes in, reports can be created with the data. 

Refrence
Real-time streaming in Power BI

Best Regards

Maggie