How Power Pivot gives optimal data models: Creating a Star Schema Model in Excel and Integrating it with Power BI. Here's how it is done:
1. Modeling a star schema in Power Pivot:
Prepare your data: Fact tables will hold measurements such as sales, income, or quantities, while dimension tables will hold descriptor attributes such as date, product, customer, or area.
Load data into Power Pivot: This includes importing tables into Power Pivot from Excel sheets, databases, or external files and using the house files.
The next step is defining relations: Use the diagram view to link the fact table with dimension tables by primary keys in Power Pivot. This results in "a star" layout, with the fact table sitting in the center while the dimension tables radiate outward.
2: Optimizing your data model:
Remove unnecessary columns, place field names, and check that all relationships are classified as one-to-many with the fact table as the side "many."
Integrating with Power BI
Export Model: Save the Excel file with the Power Pivot model.
Import into Power BI: Launch Power BI Desktop, and continue with Import Excel File. The model, including relationship information, is brought into Power BI.
Improve Reporting in Power BI: Use Power BI visualizations and reports on top of this model. Add calculated measures or KPIs in Power BI for advanced analytics.
Benefits of Star Schema in Power BI
Performance: Star schema makes queries simple with minimal table joins, which greatly improves report performance, especially with large datasets.
Clear: The structure is then easily self-explanatory for users when they see the facts and dimensions of their relationship.
Scalable: The star diagram will always be scalable to accommodate new facts and create new dimensions at any time. It would maintain the whole conceptual framework, making it easier to modify and add new facts.
More Efficient Calculations: The schema that reduces redundancy makes aggregations and calculations like SUM, AVERAGE, COUNT, etc., more efficient.
By using Power Pivot in Excel to build a star schema and tie it together with Power BI, the groundwork for better performance analytics is laid.
