DAX Measure to Switch Column Based on Selected Value

Objective

Create a DAX measure that dynamically switches between columns based on a selected value, typically used in scenarios where users need to choose which data series to display in a visual.

Approach

1. Table Setup: Ensure you have a table with multiple columns and a slicer or a selection list for users to choose the desired column.
2. SWITCH Function: Utilize the DAX SWITCH function to return the appropriate column based on user selection.

Example Scenario

Let’s assume you have a sales table with columns such as SalesAmount, Profit, and Quantity, and a segment containing the selected metric.

DAX Measure Creation

Here is a sample DAX measure:

SelectedMetric = 
VAR SelectedValue = SELECTEDVALUE(MetricSelection[Metric])
RETURN
    SWITCH(
        TRUE(),
        SelectedValue = "Sales", SUM(Sales[SalesAmount]),
        SelectedValue = "Profit", SUM(Sales[Profit]),
        SelectedValue = "Quantity", SUM(Sales[Quantity]),
        BLANK()  // Default case if no selection is made
    )

Explanation

• SELECTEDVALUE: Retrieves the value currently selected in the MetricSelection table.
• SWITCH Function: Evaluates the selected value and sums the corresponding column:
  • "Sales" returns the total sales amount.
  • "Profit" returns the total profit.
  • "Quantity" returns the total quantity sold.
• BLANK(): Used as a fallback if no valid selection is made.

Implementation Steps

1. Create a new table for metrics:
   • MetricSelection Table: Create a table with a single column containing values such as "Sales", "Profit", "Quantity".
2. Add a Slicer:
   • Use the MetricSelection table in a slicer on your Power BI report.
3. Use the Measure:
   • Incorporate the SelectedMetric measure into a visual (e.g., a card or a column chart) to display the chosen metric.

Best Practices

• Ensure that your slicer is set up correctly to reflect the possible values.
• Use descriptive naming for measures to improve readability.
• Test the measure with different selections to verify correct functionality.

Conclusion

This DAX approach enables flexibility in reporting by allowing users to select which metric to analyze, improving interactivity and user experience in data visualization. To further enhance your skills in creating dynamic DAX measures, consider exploring courses available on the Enterprise DNA Platform.