Check for Null Safely Inside a Condition in Power Query M

Explicitly tests for null before comparing, since comparing a value to null directly can behave unexpectedly in M.

Conditional LogicIntermediatenullconditionalis null

Power Query M code

let
    Source = YourTable,
    AddedStatus = Table.AddColumn(
        Source,
        "HasDiscount",
        each if [DiscountPercent] = null then false else [DiscountPercent] > 0,
        type logical
    )
in
    AddedStatus

Notes

Checking = null explicitly, rather than assuming a missing value acts as 0 or false, avoids surprises when the column mixes real values and nulls.

Requirements

How to use this snippet

  1. In Power BI Desktop, choose Transform data to open Power Query, then open the Advanced Editor on a query (or start from a blank query).
  2. Paste the snippet and replace the placeholder names (tables, columns, file paths) with your own. Check the requirements above first.
  3. Run it through the Power Query M Formatter to tidy the layout.

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