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I'm trying to rename the column headers based on the values inside the column.
To start with, I've imported CSV data from a text file (sample below), but the file doesn't have headers, so Power Query assigns generic headers: Column1, Column2, Column3
| Column1 | Column2 | Column3 |
| Online | 2/10/2022 1:30:46 AM | 299-US |
| Offline | 1/10/2019 5:01:28 AM | 458-CA |
| Online | 1/26/2022 1:49:46 PM | 284-US |
| Offline | 12/15/2021 6:24:21 AM | 296-US |
| Online | 2/4/2022 10:28:33 AM | 296-US |
Multiple people will be updating the source file, so the data might not always be in the same order, but it'll alwasy have the same information. For example, the Online/Offline column might be at the end of the table, so when it gets refreshed, it'll get assigned the header "Column3". If I rename the columns manually, then maybe next time the Online/Offline status will be in the "Account" column.
I want to rename the headers strictly based on the column values so that, for example,
This is a just sample, there are 9 columns in total so I could write a bunch of IF statements to say:
But there has to be somethign more efficient. I'm trying to find a more simple approach.
Is this possible?
Solved! Go to Solution.
You can do a transformation on the list of column names and then rename the columns based on that new list.
Here's some M code you can paste into the Advanced Editor on a new query:
let
Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("bc5BC4QgEIbhvyKei2bGUXRu0XlpITpFx4Jg8f8fV9Nagj0J8vDOtyx6jJ8jbrrR1CF0BEQKxYCwU/0rf4fQzpNem0T3vVosFoOyAijki2Xr26EvNt6U3JXlkLPvM+v5TzZtsBmjckIs6a0b3I1/c7lmId0XY550/QI=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t, Column3 = _t]),
OriginalColumnNames = Table.ColumnNames(Source),
NewColNames =
List.Transform(
OriginalColumnNames,
each if List.Contains(Table.Column(Source, _), "Offline") then "Status"
else if List.Contains(Table.Column(Source, _), "296-US") then "Account"
else _
),
UpdateColNames = Table.RenameColumns(Source, List.Zip({OriginalColumnNames, NewColNames}))
in
UpdateColNames
You can do a transformation on the list of column names and then rename the columns based on that new list.
Here's some M code you can paste into the Advanced Editor on a new query:
let
Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("bc5BC4QgEIbhvyKei2bGUXRu0XlpITpFx4Jg8f8fV9Nagj0J8vDOtyx6jJ8jbrrR1CF0BEQKxYCwU/0rf4fQzpNem0T3vVosFoOyAijki2Xr26EvNt6U3JXlkLPvM+v5TzZtsBmjckIs6a0b3I1/c7lmId0XY550/QI=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Column1 = _t, Column2 = _t, Column3 = _t]),
OriginalColumnNames = Table.ColumnNames(Source),
NewColNames =
List.Transform(
OriginalColumnNames,
each if List.Contains(Table.Column(Source, _), "Offline") then "Status"
else if List.Contains(Table.Column(Source, _), "296-US") then "Account"
else _
),
UpdateColNames = Table.RenameColumns(Source, List.Zip({OriginalColumnNames, NewColNames}))
in
UpdateColNames
Thanks Alexis - that's what I was looking for!
To take things a step further - is it possible to do the same thing but not rely on a full cell value?
Example:
IF a column has a cell values containing "296" (not the full "296-US"),
THEN rename that column to "Account"
I've tried a bunch of different ways and spent the last 6 hours searching forums but can't figure it out.
Thanks!
Try using List.MatchesAny like this:
if List.MatchesAny(Table.Column(Source, _), each Text.Contains(_, "296-US")) then "Account"
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