key aspect (BC-ESI-ESF)

Each data aspect contains business data. This business data must have one (or more) fields that uniquely identifies every aspect row. The aspect whose structure contains only those unique identifier fields is known as the key aspect. That is, each row in the key aspect uniquely identifies a row in the data aspect. Every aspect has an associated key aspect. Several aspects can share the same key aspect; each key aspect is its own key aspect.