SQL Data Exploration Project | Sales Dashboard
A portfolio case study built from pizza sales data, where SQL handled the main queries, Power Query shaped the data inside Power BI, and DAX powered the KPI measures and visuals for analysis.
Problem
The raw pizza sales data needed to be transformed into a clean reporting model that could highlight revenue, order volume, product mix, and sales trends.
Solution
I wrote the core queries in SQL, used Power Query for data shaping inside Power BI, and built the dashboard with DAX measures for the KPIs and breakdowns.
Dashboard pages
What the report shows
Executive overview
The report opens with the main KPIs: revenue, average order value, total pizza sold, total orders, and average pizzas per order.
Best and worst sellers
Top and bottom product rankings make it easy to see which pizzas drive revenue and which ones need attention.
Sales trends
Daily and monthly trends show when demand peaks across the year, supporting planning and performance reviews.
Category and size mix
Category and size visuals show customer preference patterns and the sales mix at a glance.
How it was built
Query the dataset in SQL
I used SQL to prepare the dataset and shape the base fields that feed the reporting model.
- Load the source tables and validate the structure
- Standardize fields for analysis
- Remove inconsistencies and duplicates
- Prepare a reporting-ready dataset
Shape the model in Power Query
Power Query handled the transformations inside Power BI so the model stayed clean and ready for analysis.
- Apply transformations inside Power BI
- Refine data types and column logic
- Prepare the model for analysis
- Keep the reporting layer lean and reliable
Build KPI measures in DAX
DAX powered the KPI cards, category splits, and ranking visuals used in the report.
- Calculate revenue and order metrics
- Build measures for totals and averages
- Support top and bottom seller analysis
- Power the dashboard visuals
Deliver the dashboard narrative
The final output is a business-friendly dashboard that turns raw pizza sales data into clear, actionable insights.
- Executive dashboard design
- Clear KPI structure
- Data storytelling
- Decision support for business users
Tools and technologies
Why it matters
- How to move from raw data to reporting-ready outputs
- How SQL, Power Query, and DAX work together in one reporting flow
- How Power BI turns metrics into a clear business story
- How to communicate data findings in a portfolio-friendly format