The TRADE_MAPPING table maps trades/positions to books and legal entities by TRADE_ID and AS_OF_DATE.The multi-level book organizational hierarchy and desk descriptions are in the BOOK_HIERARCHY table which is indexed by BOOK and AS_OF_DATE.The multi-level legal entity organizational hierarchy is in the LEGAL_ENTITY_HIERARCHY table which is indexed by LEGAL_ENTITY and AS_OF_DATE.
It is built from the table.The LEGAL_ENTITY_ATTRIBUTES table provides a description of the legal entities.