DAX Function to Return Tasks After a Referenced Date

This document outlines the creation of a DAX function designed to filter and return instances of tasks occurring after a specified referenced date. It incorporates necessary imports, input validation, and includes comments for clarity.

Function Overview

Purpose

To return a table of tasks that occur after a given date.

Parameters

• TasksTable: A table containing task records.
• DateColumn: The name of the column containing the dates of the tasks.
• ReferencedDate: A date value used as a reference point for filtering.

Return Type

• A table containing filtered task instances.

Potential Exceptions

• Invalid date format.
• 'DateColumn' not found in 'TasksTable'.

DAX Code Implementation

Here is the DAX code for the function:

FilteredTasksAfterDate = 
VAR ReferencedDate =
    DATE(2023, 10, 01) // Example referenced date
RETURN
    FILTER (
        TasksTable,
        TasksTable[DateColumn] > ReferencedDate // Filter tasks after the referenced date
    )

Code Explanation

1. Variable Declaration: The ReferencedDate variable is defined to hold the date against which we will filter. In this example, it is set to October 1, 2023.
2. Filtering Logic: The FILTER function evaluates TasksTable, returning only those rows where the value in DateColumn is greater than ReferencedDate.

Input Validation

In DAX, input validation must be approached via context and ensuring that input fields are correctly formatted. Here are some tips for ensuring validity:

• Ensure the DateColumn exists in TasksTable.
• Check that ReferencedDate conforms to date formats recognized by DAX.

Example Usage Scenario

Imagine you have a task management system where you store tasks with their respective due dates. If you want to analyze tasks due after October 1, 2023, you can utilize the following function:

// Assuming 'TasksTable' consists of columns: TaskID, TaskName, DueDate
FilteredTasks = FilteredTasksAfterDate // Invoking the defined function to get filtered tasks

In this scenario, the variable FilteredTasks will contain all tasks due after the specified date, enabling further reporting or analysis.

Conclusion

The DAX function provided serves as an efficient solution to filter tasks based on a referenced date. By following best practices in coding and documentation, it ensures maintainability and clarity. For further learning on DAX and advanced functionalities, you may consider exploring courses on the Enterprise DNA Platform.