PL-300 Visualize and analyze the data Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Create a calculated column that flags last 12 months.

  Why it's wrong here

  A calculated column that flags the last 12 months is generated during data load or refresh, so its values become static once computed. As time progresses, the column's flagging logic does not automatically shift to reflect the new current date, causing outdated results unless the dataset is refreshed. Moreover, even after a refresh, the column only marks rows based on the refresh-time boundary, whereas a relative date filter dynamically recalculates the window at query time.

• ✗

  Add a slicer for the last 12 months.

  Why it's wrong here

  A slicer for the last 12 months only adds a visual control that lets users manually choose a date range, but it does not automatically filter the report to the last 12 months. The requirement demands that the visual itself displays the sales trend for the trailing year without any user interaction, so relying on a slicer leaves the visual unfiltered until a user explicitly selects the option. Additionally, a slicer typically requires the user to know the specific date range or use a preset, which does not guarantee a consistent, dynamic last-12-month view.

• ✗

  Write a measure that calculates sales for last 12 months and use it in a visual.

  Why it's wrong here

  Writing a measure that calculates sales for the last 12 months provides a single scalar value, such as total sales, but it does not constrain the rows displayed in a trend visual. A line or column chart needs each data point (e.g., each month) to be filtered to the last 12 months, and a measure has no effect on which dates are included in the visual's axis. Without a separate date filter, the visual will still show all dates in the underlying table, and the measure will just return a value for the entire period or be evaluated in the visual's context, not automatically restrict the trend to the trailing year.

• ✓

  Use a relative date filter on the date field set to 'Last 12 months'.

  Why this is correct

  A relative date filter on the date field set to 'Last 12 months' directly applies a dynamic query-time filter that includes exactly the trailing 12 complete months (or periods) relative to the current date. This filter automatically shifts as time advances, so the visual always reflects the most recent 12 months without requiring manual updates or user interaction. It is the correct approach because it operates at the filter level, ensuring every visual using that date field is restricted to the desired window while still allowing the underlying measures to calculate correctly within that context.

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