[Solved] You wrote this M code:let Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content], Promoted = Table.PromoteHeaders(Source, [PromoteAllScalars=true]) in PromotedBut the headers did not change.... | Power BI

Power BI - Data Cleaning with Power Query

You wrote this M code:

let
  Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
  Promoted = Table.PromoteHeaders(Source, [PromoteAllScalars=true])
in
  Promoted

But the headers did not change. What is the likely cause?

ATable.PromoteHeaders requires a second argument to work

BThe PromoteAllScalars option is invalid and causes failure

CThe first row is already headers, so no change occurs

DThe Source table is empty, so promotion fails

Step-by-Step Solution

Solution:

Step 1: Understand PromoteHeaders behavior
If the first row is already headers, promoting headers again does not change anything.
Step 2: Check the options and source
PromoteAllScalars is a valid option; empty source would cause errors; second argument is optional.
Final Answer:
The first row is already headers, so no change occurs -> Option C
Quick Check:
No change if headers already promoted [OK]

Quick Trick: No effect if headers already promoted [OK]

Common Mistakes:

Master "Data Cleaning with Power Query" in Power BI

9 interactive learning modes - each teaches the same concept differently

More Power BI Quizzes

You wrote this M code: