Developer Transformation Guide > Aggregator Transformation > Aggregator Transformations in Dynamic Mappings
  

Aggregator Transformations in Dynamic Mappings

You can use an Aggregator transformation in a dynamic mapping. You can configure dynamic ports in the transformation and reference the generated ports.
You can perform the following tasks to configure an Aggregator transformation in a dynamic mapping:
Reference a dynamic port or a generated port as a Group By column.
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.
Reference a generated port in the aggregate expression.
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.
Create the aggregate expression in an output port.
You cannot create an aggregate expression in a generated port or a dynamic port. The aggregate expression cannot be a dynamic expression.
Parameterize values in the aggregate expression.
You can include parameters in the aggregate expresson. However, You cannot use an expression parameter or a port parameter in the aggregate expression.