You can include dynamic ports or generated ports as Group By columns. If you specify a dynamic port as a Group By column, you are specifying that all generated ports in the dynamic port are Group By columns. For this reason, you cannot specify a generated port as a Group By column if you specified the parent dynamic port as a Group By column. If you reference a generated port, and the generated port does not exist at run time, the mapping fails. You can parameterize the Group By columns to indicate which columns to group at run time.

You can include a generated port in the aggregate expression. If the port does not exist at run time, the mapping fails. You cannot reference a dynamic port in the aggregate expression.

You cannot create an aggregate expression in a generated port or a dynamic port. The aggregate expression cannot be a dynamic expression.

You can include parameters in the aggregate expresson. However, You cannot use an expression parameter or a port parameter in the aggregate expression.