Question

In Power Query, you are cleaning a Products table. You need a new column that contains the uppercase version of the existing 'ProductName' column while keeping the original column unchanged. You select the ProductName column and go to the Add Column tab, then Format > UPPERCASE. However, after applying, you notice the original ProductName values were converted to uppercase instead of a new column being added. What most likely caused this behavior?

Accepted Answer

You used the Transform tab's Format > UPPERCASE option, which modifies the selected column in place rather than adding a new one.

Answer

The Add Column tab's Format option always overwrites the source column when the data type is Text.

Answer

Power Query cannot create a new column from a text transformation; you must use Column From Examples instead.

Answer

The applied step failed silently, so Power Query defaulted to modifying the existing column.