Later, you'll learn how to connect Power BI directly to SQL databases and other enterprise sources.
🔹 7. Importing Data
A typical process is:
Home
↓
Get Data
↓
Choose Source
↓
Select Table/File
↓
Transform Data
↓
Load
Don't immediately start creating charts.
First understand:
What data did I load?
🔹 8. Power Query
Power Query is Power BI's data preparation and transformation engine.
You'll use it to:
• Remove unwanted columns
• Rename columns
• Change data types
• Remove duplicates
• Handle missing values
• Split columns
• Merge tables
• Append tables
• Filter rows
• Create transformation steps
This is similar to the Power Query work you learned in Excel.
The important idea is:
Power Query prepares the data before analysis.
🔹 9. Power Query vs DAX
This distinction is extremely important.
Power Query
→ Used mainly for data preparation and transformation
DAX
→ Used mainly for calculations and analysis inside the data model
Think:
Power Query
"Prepare the data."
DAX
"Analyze the data."
You'll learn both in detail in later parts.
🔹 10. Data Modeling
Suppose you have:
Sales
• Order_ID
• Customer_ID
• Product_ID
• Date
• Sales
Customers
• Customer_ID
• Customer_Name
• Region
Products
• Product_ID
• Product_Name
• Category
Date
• Date
• Month
• Quarter
• Year
Instead of putting everything into one giant table, Power BI can connect these tables through relationships.
This is called data modeling.
🔹 11. Relationships
For example:
Customers
Customer_ID
↓
Sales
↑
Product_ID
Products
The relationship allows Power BI to understand how tables are connected.
For example:
Customer → Sales
allows you to analyze sales by customer region.
Product → Sales
allows you to analyze sales by product category.
🔹 12. Fact Tables and Dimension Tables
A common data-modeling structure is the star schema.
At the center:
⭐ Fact Table
Around it:
🔹 Dimension Tables
Example:
Customers
Products — Sales — Date
Region
The "Sales" table contains business events or measurements.
The dimension tables provide descriptive context.
This structure is extremely important for Power BI.
🔹 13. Measures vs Columns
Another fundamental concept.
Suppose you have:
"Sales"
A calculated column could calculate something for each row.
A measure calculates a value based on the current report context.
Example measure:
Total Sales =
SUM(Sales[Sales_Amount])
When you put this measure into a visual, Power BI calculates it according to the selected:
• Region
• Product
• Date
• Customer
• Filters
This makes measures extremely powerful.
🔹 14. Your First Visualization
Suppose you have:
Month| Sales
Jan| 100,000
Feb| 120,000
Mar| 150,000
You could create a line chart.
The chart immediately communicates:
📈 Sales are increasing over time.
But visualization choice matters.
You shouldn't select a chart because it looks attractive.
Choose it because it communicates the business message clearly.
🔹 15. Common Power BI Visuals
You should become familiar with:
📊 Bar Chart
📈 Line Chart
🥧 Pie / Donut Chart
🔢 Card
📋 Table
📑 Matrix
🎯 KPI
🗺️ Map
📊 Column Chart
🎛️ Slicer
Each visual serves a different analytical purpose.
🔹 16. Cards
Cards are useful for displaying important KPIs.
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