The Insert Stream operator converts a relation into a stream. When the insert stream operation is triggered, all changed or new records are issued.
In other words, the Insert Stream operator passes new records, unlike the Relation Output operator, which issues individual records tagged with either a plus (+), meaning a new record, or taggied with minus (-), meaning a record that was issued previously, but is no longer part of the relation result.
If you want to output data from the IEP process, use the Insert Stream operator and connect it to a Stream Output operator.
To create an Insert Stream operator: