Methodology to transform a changing quantity of columns

[TomasBA]

I have a initial table with a variable quantity of columns, I would like to transform the columns making the operation robust, i.e not depending on the column names.
Function to be applied on all columns: extraction of the first character

Technique intended : make a list with the existing column names and apply the transformation to the list of columns.

Which is the efficient method to do so?

[v-stephen-msft · Accepted solution]

Hi @TomasBA ,

Try the Text.Start function. It returns the first count characters of text as a text value.

Text.Start - PowerQuery M | Microsoft Learn

And then try pivot/unpivot.

Pivot columns - Power Query | Microsoft Learn

Unpivot columns - Power Query | Microsoft Learn

Best Regards,

Stephen Tao

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