Explain the Table Calculation Function 'WINDOW_MAX() in Tableau with Example?

 The WINDOW_MAX() function in Tableau is a table calculation function that calculates the maximum value of a given field or expression over a specified window or range of values. It identifies the largest value within the defined window.

The syntax for the WINDOW_MAX() function in Tableau is as follows:

WINDOW_MAX(expression, [start, end])

• expression: The field or calculation for which you want to calculate the maximum value.
• start (optional): The starting point of the window. If not specified, the window starts from the first data point.
• end (optional): The ending point of the window. If not specified, the window ends at the current data point.

Here's an example to demonstrate how to use the WINDOW_MAX() function in Tableau:

Suppose you have a dataset that contains information about the monthly sales of different products. You want to identify the maximum sales value within a rolling three-month window.

1. Open Tableau and connect to your dataset.
2. Create a view that includes the "Date" field and the "Sales" field.
3. Right-click on the "Sales" field and select "Add Table Calculation."
4. In the calculation dialog box, choose "MAX" from the list of table calculation functions.
5. Specify the expression as the field or calculation for which you want to calculate the maximum value (in this case, "Sales").
6. Configure the specific settings for the WINDOW_MAX function, such as the addressing and partitioning options, to define the rolling three-month window.
7. Click "OK" to apply the WINDOW_MAX function to the sales values.

Tableau will calculate the maximum sales value within the specified rolling three-month window. It identifies the largest sales value among all the sales values within the window.

You can further customize the view, apply sorting, or add additional calculations based on the maximum value. For example, you can create a visualization that shows the trend of the maximum sales value over time or compare the maximum values across different products.

The WINDOW_MAX function allows you to perform calculations related to finding the maximum value within a specified window. It helps you identify the highest value within a dataset and supports various data analysis and visualization scenarios.