Unpivoting columns in Power BI - Dashboard Guide

Dashboard Mode - Unpivoting columns

Business Question

How can we transform monthly sales data from columns into rows to analyze sales trends easily?

Sample Data: Monthly Sales by Product

Product	Jan	Feb	Mar
Apples	100	120	130
Bananas	80	90	95
Cherries	50	60	70
Dates	40	45	50
Elderberries	30	35	40

Dashboard Components

• Unpivoted Table: Shows sales data with columns Product, Month, and Sales. This is created by unpivoting the Jan, Feb, and Mar columns into rows.
• Total Sales by Month (KPI Card): Displays total sales for each month.
  Formula (DAX measure):
  Total Sales = SUM('UnpivotedData'[Sales])
• Sales Trend Line Chart: X-axis: Month, Y-axis: Sales, Legend: Product. Shows how sales change over months for each product.

Dashboard Layout

+----------------------+---------------------+
| Total Sales by Month | Sales Trend Line    |
|      (KPI Card)      |      (Line Chart)   |
+----------------------+---------------------+
|                Unpivoted Table               |
+----------------------------------------------+

Interactivity

Adding a slicer for Product allows filtering the unpivoted table, KPI card, and line chart to show data only for the selected product(s). Selecting a month in the line chart highlights sales for that month in the table and updates the KPI card accordingly.

Self Check

If you add a filter to show only Product = Bananas, which components update and what changes occur?

• The unpivoted table shows only rows for Bananas with months Jan, Feb, Mar and their sales.
• The Total Sales KPI card updates to show the sum of Banana sales for all months (80 + 90 + 95 = 265).
• The Sales Trend Line Chart shows only the Banana sales trend over the three months.

Key Result

Dashboard showing monthly sales trends by unpivoting monthly columns into rows for easy analysis.

Practice

1. What does unpivoting columns in Power BI do?

easy

A. It merges multiple tables into one table.

B. It filters rows based on column values.

C. It creates new calculated columns based on existing data.

D. It converts multiple columns into rows to simplify analysis.

Solution

1. Step 1: Understand the purpose of unpivoting

   Unpivoting changes the data layout by turning columns into rows, making repeated measures easier to analyze.

2. Step 2: Compare with other operations

   Merging tables combines tables, calculated columns add new data, and filtering removes rows, which are different from unpivoting.

3. Final Answer:

   It converts multiple columns into rows to simplify analysis. -> Option D

4. Quick Check:

   Unpivoting = Columns to rows [OK]

Hint: Unpivoting flips columns into rows for easier data analysis [OK]

Common Mistakes:

• Confusing unpivoting with merging tables
• Thinking unpivoting creates new columns
• Assuming unpivoting filters data

2. Which step correctly describes how to unpivot columns in Power Query Editor?

easy

A. Select the columns to unpivot, right-click, and choose 'Unpivot Columns'.

B. Select the columns, then click 'Merge Queries'.

C. Select the columns, then click 'Add Column' > 'Custom Column'.

D. Select the columns, then click 'Remove Columns'.

Solution

1. Step 1: Identify the unpivot action in Power Query

   Unpivoting is done by selecting columns, right-clicking, and choosing 'Unpivot Columns'.

2. Step 2: Differentiate from other options

   'Merge Queries' combines tables, 'Add Column' creates new columns, and 'Remove Columns' deletes columns, none unpivot data.

3. Final Answer:

   Select the columns to unpivot, right-click, and choose 'Unpivot Columns'. -> Option A

4. Quick Check:

   Unpivot = Right-click > Unpivot Columns [OK]

Hint: Right-click selected columns and pick 'Unpivot Columns' [OK]

Common Mistakes:

• Choosing 'Merge Queries' instead of unpivot
• Trying to add a custom column to unpivot
• Removing columns instead of unpivoting

3. Given this table before unpivoting:

Product | Jan | Feb | Mar
--------|-----|-----|----
A       | 10  | 15  | 20
B       | 5   | 7   | 8

What will be the result after unpivoting the Jan, Feb, Mar columns?

medium

A. Product | Month | Sales
--------|-------|------
Jan | A | 10
Feb | A | 15
Mar | A | 20
Jan | B | 5
Feb | B | 7
Mar | B | 8

B. Product | Jan | Feb | Mar
--------|-----|-----|----
A | 10 | 15 | 20
B | 5 | 7 | 8

C. Product | Attribute | Value
--------|-----------|------
A | Jan | 10
A | Feb | 15
A | Mar | 20
B | Jan | 5
B | Feb | 7
B | Mar | 8

D. Product | Value
--------|------
A | 10
A | 15
A | 20
B | 5
B | 7
B | 8

Solution

1. Step 1: Understand unpivot output structure

   Unpivoting converts columns Jan, Feb, Mar into rows under a new 'Attribute' column, with their values in 'Value'.

2. Step 2: Match the correct table format

   Product | Attribute | Value
   --------|-----------|------
   A       | Jan       | 10
   A       | Feb       | 15
   A       | Mar       | 20
   B       | Jan       | 5
   B       | Feb       | 7
   B       | Mar       | 8

   shows Product repeated with each month as 'Attribute' and corresponding values, which matches unpivot output.

3. Final Answer:

   Table with columns Product, Attribute, Value listing each month as a row. -> Option C

4. Quick Check:

   Unpivot = Columns to Attribute-Value rows [OK]

Hint: Unpivot creates Attribute and Value columns from selected columns [OK]

Common Mistakes:

• Thinking unpivot keeps original columns
• Dropping the attribute column
• Swapping row and column values incorrectly

4. You tried to unpivot columns in Power Query but the 'Unpivot Columns' option is greyed out. What is the most likely cause?

medium

A. You are in the Data view instead of Power Query Editor.

B. You have not selected any columns to unpivot.

C. Your data contains blank rows.

D. Your table has too many columns.

Solution

1. Step 1: Check selection requirement for unpivot

   The 'Unpivot Columns' option requires at least one column selected; otherwise, it is disabled.

2. Step 2: Eliminate other causes

   Blank rows or table size do not disable the option; being outside Power Query Editor means the option is not visible, not greyed out.

3. Final Answer:

   No columns selected to unpivot. -> Option B

4. Quick Check:

   Unpivot disabled if no columns selected [OK]

Hint: Always select columns before unpivoting [OK]

Common Mistakes:

• Ignoring the need to select columns
• Confusing Power Query Editor with Data view
• Assuming blank rows disable unpivot

5. You have sales data with columns: Region, Product, Q1, Q2, Q3, Q4. You want to analyze quarterly sales trends by region and product. Which is the best approach?

hard

A. Unpivot the Q1, Q2, Q3, Q4 columns to create a 'Quarter' and 'Sales' column.

B. Merge the Q1 to Q4 columns into one column using concatenation.

C. Create calculated columns for each quarter's sales growth.

D. Filter the data to show only Q1 and Q2 sales.

Solution

1. Step 1: Identify the need for unpivoting

   Quarterly sales are spread across columns Q1 to Q4; unpivoting these columns will convert them into rows with 'Quarter' and 'Sales' columns, enabling trend analysis.

2. Step 2: Evaluate other options

   Merging columns concatenates data, which is not useful for numeric analysis; calculated columns for growth require unpivoted data first; filtering limits data and does not reshape it.

3. Final Answer:

   Unpivot the Q1, Q2, Q3, Q4 columns to create a 'Quarter' and 'Sales' column. -> Option A

4. Quick Check:

   Unpivot quarterly columns for trend analysis [OK]

Hint: Unpivot repeated measure columns for time series analysis [OK]

Common Mistakes:

• Trying to merge numeric columns as text
• Skipping unpivot before calculating growth
• Filtering instead of reshaping data