If you want to view a Power BI Report with Large Datasets in it without compromising the Slow Performance of the Report, Employ the Following Strategies:
Data-extraction methods: First, transfigure only the data needed into Power BI. Then, Deploy filters at the source to reduce the dataset's size. For instance, if I am working with sales data and want to analyze sales by region, I would extend the data limitation to years when such areas were available. This would remove a lot of data that Power BI would have dealt with, hence enhancing the speed of report generation.
Optimized data model: Logically structure your data by constructing a star schema as opposed to using a flat table design. A star schema is one where the fact tables, such as sales transactions, are kept separate from the dimension tables that contain information about customers and products. This design helps in enhancing the reports because the publication of data processing is faster in Power BI.
Streamlined DAX expressions: Do not attempt to prevent the rational use of time for unnecessary calculations done in DAX that are not helpful. Instead, do that in the data source whenever you can. If one needs to calculate sales as of date for numerous periods, do not – within Power BI – create a DAX measure; rather, add a column in the source database.
When used together, all the above strategies guarantee that reports created in Power BI will work with heavy datasets without any performance issues.