Column / Bar Chart

Introduction

The Column Chart and Bar Chart widgets allow you to compare values across categories using rectangular bars.

• Column Chart - Vertical bars (categories on the X-axis, values on the Y-axis).
• Bar Chart - Horizontal bars (categories on the Y-axis, values on the X-axis).

These charts are among the most common visualization types, making it easy to compare values and identify patterns.

Purpose

To compare values across categories.

They are particularly effective when you want to:

• Compare different categories (e.g., sales of product categories).
• Show relative contribution (proportions) of sub-categories using a stacked Column/Bar Chart.
• Use Bar Chart when category names are long or when you have many categories.
• Use Stacked/Grouped mode to see both totals and category breakdowns.

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Steps to Create a Column / Bar Chart

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

   

2. A widget will be automatically added to the edit screen.

   

3. Select Dataset

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

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

     

Sample Dataset (ProductSales.ds)

OrderDate	Year	Quarter	Month	ProductCategory	ProductSubCategory	Sales	ColorHex
2023-01-15	2023	Q1	Jan	Electronics	Laptops	12000	#1f77b4
2023-02-20	2023	Q1	Feb	Electronics	Smartphones	8500	#2ca02c
2023-04-10	2023	Q2	Apr	Appliances	Kitchen	7000	#ff7f0e
2023-05-25	2023	Q2	May	Electronics	Laptops	15000	#1f77b4
2023-08-05	2023	Q3	Aug	Appliances	Laundry	6500	#9467bd

4. Select Chart Type

   • From the Chart Type dropdown in the Type panel, choose Column or Bar.

5. Assign Category Axis

   • Drag a categorical column to the Category Axis field.
   • Defines the categories along the horizontal axis (Column Chart) or vertical axis (Bar Chart).
   • Example: ProductCategory, ProductSubCategory

6. Assign Value Axis

   • Drag a numerical column into the Value Axis field.
   • Determines the bar length/height.
   • Example: Sales

7. Configure Aggregator

   • Click on the icon next to the Value Axis 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 – Series

   • Drag another categorical column into the Series field.
   • Example: Compare ProductSubCategory within each ProductCategory.
   • By default, it creates a grouped bar chart, but you can switch to a stacked bar chart by enabling the Stack option under General.

9. Optional – Color by Column

   • Assign colors by dragging a categorical column here.

   • Example: Color by ProductCategory.

     

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Common Functionalities (Properties Panel)

• General
  
• Category Axis: Labels, ticks, display range.
• Value Axis: Scale, labels, display range.
• Series
  
• Legend
  
• Tooltip
  

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Use Case: Employee Performance

Introduction

The Employee Performance use case demonstrates how Column and Bar Charts can be applied to HR or organizational datasets. By visualizing employee scores across departments, managers can easily compare overall department performance and identify top contributors.

Sample Dataset (StudentMarks.ds)

Year	Student	Subject	Marks
2023	Alice	Math	85
2023	Alice	Science	90
2023	Bob	Math	78
2023	Bob	Science	82
2023	Charlie	Math	92
2023	Charlie	Science	88
2024	Alice	Math	88
2024	Alice	Science	93
2024	Bob	Math	81
2024	Bob	Science	85
2024	Charlie	Math	95
2024	Charlie	Science	90

How to Configure

• Enter the following details for the Column or Bar Chart Widget:

  • Datasets (ds) -> StudentMarks.ds

  • Chart Type -> Column Chart

  • Category Axis -> Student

  • Value Axis -> Marks

  • Aggregator -> Sum

  • Optional Series -> Year (to see stacked bar chart or grouped bar chart contributions)

    

Summary

The Student Marks use case illustrates how Column and Bar Charts can provide insights into academic performance.

• Column Chart -> Quick comparison of students’ marks across years.
• Bar Chart -> Useful when student names or subject labels are long.
• Stacked/Grouped Charts -> Help visualize both total marks and individual year-wise contributions for each student.