Power BI – Sales Data Modeling and DAX

This project demonstrates a complete data modelling workflow in Power BI using DAX and data transformation techniques.

Dataset & Model

• Fact table: Sales, connected to dimension tables for Customers, Products, and Regions.
• Custom Date Dimension (DimDate) created with CALENDARAUTO() and enriched with Year, Month, YearMonth and more.
• Customer segmentation by age group: 0–20, 21–30, 31–40, and >41.

Key DAX Measures

• Total Sales, Profit, Profit Margin, Sales YTD
• Monthly Growth and Year over Year (YoY) metrics
• Customer insights: Average Sales per Customer, Unique Users

Report Highlights

• Two report tabs: Sales Overview and Customer/Product Profiles

• Interactive visualizations driven by DAX measures and data transformations

Optimization & Challenges

Model optimization included replacing calculated columns with DAX measures to improve performance. Difficulties were faced with date-based calculations and region-customer relationships due to incomplete source data.