How do people represent Usagi mappings in Rabbit-in-a-hat?
The use of a Stem_table does not appear to allow this, so how does the ETL developer receive guidance on making the appropriate joins to the source_to_concept_map?
I draw an arrow from the source value to the concept id column and put the information about how to join in the logic section.
Rabbit in a Hat currently offers no integration with Usagi. As Don said, typically the guidance is put in the logic section of the field mapping from source code to target concept_id.