Replacing values in multiple columns based on condition in Power Query

Hi, Anonymous 

Based on the simulated data source and the data processing logic you provided, write the query code like this:

= Table.ReplaceValue(Source, each [day flag]="Down Day", null, (x,y,z)=> if y then z else x, List.Range(Table.ColumnNames(Source),1,4))

If my code solves your problem, mark it as a solution

Hi, Anonymous 

As what is suggested by ziying35 , I created data to reproduce your scenario. The pbix file is attached in the end.

Table:

You may insert a new step as below. On your side, you may add all corresponding columns in {"plan","unplan","internal","external",...}.

= Table.ReplaceValue(Source, each [day flag]="Down Day", null, (x,y,z)=> if y then z else x, List.Select(Table.ColumnNames(#"Changed Type"),
each  List.Contains( {"plan","unplan","internal","external"},_)
)
)

Result:

Best Regards

Allan

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.