Pie / Donut Chart

Introduction

The Pie Chart and Donut Chart widgets allow you to visualize proportions of a whole.
Each slice represents a category’s contribution relative to the total.

• Pie Chart – Circular chart divided into slices.
• Donut Chart – Similar to a pie chart but with a hole in the middle for a modern look or to display totals.

These charts are best for showing percentage or proportional data at a glance.

Purpose

To show proportions of categories within a whole.

They are particularly effective when you want to:

• Highlight relative contribution of each category.
• Show percentage breakdowns rather than absolute values.
• Use Donut Chart for better readability when you also want to show the total in the center.
• Avoid when there are too many categories, as slices become difficult to compare.

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Steps to Create a Pie / Donut Chart

1. From the left vertical menu, select the Charts icon.

   

2. A widget will be automatically added to the Viz canvas.

   

3. Select Dataset

   • From the Datasets dropdown, choose your dataset (e.g., MarketShare.ds).

   • Available columns will be displayed in the Available Columns panel.

     

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Sample Dataset (MarketShare.ds)

Company	Sales
Alpha Corp	45000
Beta Ltd	30000
Gamma Inc	20000
Delta Co	15000
Epsilon Group	10000

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Configuration Steps

4. Select Chart Type

   • From the Type dropdown in the Properties Panel, choose Pie or Donut.

5. Assign Category Field

   • Drag a categorical column to the Category field.
   • Defines the slices of the chart.
   • Example: Company

6. Assign Value Field

   • Drag a numerical column into the Values field.
   • Determines the size of each slice.
   • Example: Sales

7. Configure Aggregator

   • Click on the icon next to the Values field.
   • Choose an Aggregator to define how values are calculated:
     • Count – Number of records.
     • Distinct Count – Unique count of records.
     • Sum – Total of all values.
     • Average – Mean value.
     • Min – Minimum value.
     • Max – Maximum value.

8. Optional – Color by Column

   • Assign colors by dragging a categorical column here.

   • Example: Color by Company.

     

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Common Functionalities (Properties Panel)

• General
  
• Labels: Show/hide category names, values, or percentages.
• Colors: Configure custom palette for slices.
• Legend
  
• Tooltip
  

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Use Case: Employee Performance

Introduction

The Employee Performance use case demonstrates how Pie and Donut Charts can show proportional contributions. By visualizing department-level shares, managers can easily identify which areas contribute most to overall performance.

Sample Dataset (EmployeePerformance.ds)

Department	Employee	Score
Sales	John	85
Sales	Mary	90
HR	Anita	75
HR	Rahul	82
IT	Sanjay	95
IT	Priya	88

How to Configure

• Category -> Department

• Value -> Score (Aggregator = Sum)

  

Business Questions Answered

• Pie Chart -> What percentage of the total performance score does each department contribute?
• Donut Chart -> Which department contributes most, and how does the total look in the center?
• Employee-level Pie Chart -> How do individual employees contribute to the total departmental performance?

Summary

The Employee Performance use case illustrates how Pie and Donut Charts can provide insights into proportions.

• Pie Chart -> Best for simple breakdowns of a few categories.
• Donut Chart -> More modern look and supports showing totals in the center.
• Employee/Department slices -> Help identify major contributors at both levels.