The Insert Stream operator converts a relation into a stream.
When the Insert Stream operation is triggered, all changed or new records are issued as output.
The Insert Stream operator passes new records as output. In contrast, the Relation Output operator issues individual records tagged with either a plus, meaning a new record, or minus, meaning a record that was issued previously but is no longer part of the relation result.
Use the Insert Stream operator when you want to pass new or changed records into the output stream.