What do hidden columns in an Aggregate do to the output?

The role of hidden columns in an Aggregate is to allow developers to utilize specific data for internal processes or logic without displaying those columns in the final output set. When a column is marked as hidden, it does not get included in the output that is sent to the client or the front-end of the application. Instead, hidden columns can still be used internally for calculations, conditions, or as part of data manipulation within the aggregate.

The impact of hidden columns is primarily seen when previewing data within the development environment. They allow developers to view the data without exposing it to the end user. This can help in debugging or refining logic, ensuring that the necessary data is processed while keeping the user interface clean and relevant to the user’s needs. Thus, the correct answer is that hidden columns affect the preview, meaning they do not appear in the final output sent to the client but can be accessed while developing.