Data Visualization in Power BI

Key Concepts

• Visual Types: Different types of charts and graphs available in Power BI.
• Custom Visuals: Additional visuals that can be imported and used in Power BI.
• Data Roles: The roles that data plays in a visual, such as axis, legend, and values.
• Visual Interactions: How visuals can interact with each other on a report page.

Visual Types

Power BI offers a variety of visual types to represent data, including bar charts, line charts, pie charts, scatter plots, and more. Each visual type is suited for different types of data and analysis.

Example: A bar chart is ideal for comparing categorical data, while a line chart is better for showing trends over time.

        // Example of creating a bar chart in Power BI
        Select "Bar Chart" from the Visualizations pane.
        Drag "Category" to the Axis field.
        Drag "Sales Amount" to the Values field.
    

Custom Visuals

Custom visuals are additional visual types that can be imported into Power BI from the marketplace. These visuals provide more specialized ways to represent data, such as heat maps, gauge charts, and more.

Example: If you need to represent data in a geographical context, you can import a custom map visual from the Power BI marketplace.

        // Example of importing a custom visual in Power BI
        Go to the "Visualizations" pane.
        Click on the ellipsis (...) and select "Get more visuals."
        Search for "Map" and click "Add" to import the custom map visual.
    

Data Roles

Data roles define how data is used in a visual. Common roles include Axis, Legend, and Values. Understanding these roles helps in correctly configuring visuals.

Example: In a pie chart, the Category data role is used for the slices, while the Values data role is used for the size of each slice.

        // Example of configuring data roles in a pie chart
        Select "Pie Chart" from the Visualizations pane.
        Drag "Category" to the Legend field.
        Drag "Sales Amount" to the Values field.
    

Visual Interactions

Visual interactions allow you to control how visuals on a report page interact with each other. You can set visuals to filter, highlight, or cross-filter each other.

Example: If you have a bar chart and a line chart on the same page, you can set the bar chart to filter the line chart, so selecting a bar in the bar chart will filter the data in the line chart.

        // Example of setting visual interactions in Power BI
        Select the bar chart.
        Go to the "Format" tab.
        Click on "Edit Interactions."
        Set the interaction type between the bar chart and the line chart to "Filter."