IMO there are areas where the documentation needs to be improved to help everybody not invent new solutions. This discussion is centering around the definition of a musical work and its’ structure. As a starter, I find the following structure helpful (I’ve no particular attachment to the terminology, just the structure) all of them are currently MB works:
“Classes of Work”
-
“Component Works”
-
“Top-Level Works”
-
“Collection Works”
“Component Work” definition. A “Component Work” is a work which may be performed on its own, but is often performed and was composed (or otherwise produced) as part of a larger work. “Component works” may themselves be composed of “Component Works” where there is a need for several levels of hierarchy.
“Top-Level Work” definition. A “Top-Level work” is a work which was composed, and is often performed, as an entity. A “Top-Level Work” will normally be an entry in a composers catalogue of works; such an identifier may well be an opus number and a serial number. A “Top-Level Work” is often a collection of “Component Works”
“Collection Works” definition. A “Collection Work” is set of works which are related either by the composer, cataloger, or publisher. They are sometimes performed as an entity, typically related to an event. A “Collection Work” is always a collection of “Top-Level Works” or possibly other “Collection Works”.
A part / part of relation connects “Component Works” and “Top-Level Works”.
A member / member of relation connects "“Top-Level Works” and “Collection Works”.
Examples:
Rigoletto: Atto II. “Povero Rigoletto!” (Marullo, Rigoletto, Coro, Borsa, Ceprano, Paggio) - is a "Component Work"
Rigoletto: Atto II - is a "Component Work"
Rigoletto - is a "Top-Level Work"
Rigoletto: Atto II. “Povero Rigoletto!” (Marullo, Rigoletto, Coro, Borsa, Ceprano, Paggio) is “part of” Rigoletto: Atto II
Rigoletto: Atto II “part of” Rigoletto
Sonata for Piano no. 14 in C-sharp minor, op. 27 no. 2 “Moonlight”: I. Adagio sostenuto - is a "Component Work"
Sonata for Piano no. 14 in C-sharp minor, op. 27 no. 2 “Moonlight” - is a "Top-Level Work"
Two Piano Sonatas, op. 27 - is a "Collection Work"
Sonata for Piano no. 14 in C-sharp minor, op. 27 no. 2 “Moonlight”: I. Adagio sostenuto is “part of” Sonata for Piano no. 14 in C-sharp minor, op. 27 no. 2 "Moonlight"
Sonata for Piano no. 14 in C-sharp minor, op. 27 no. 2 “Moonlight” is a “member of” Two Piano Sonatas, op. 27
Götterdämmerung, WWV 86D - is a "Top-Level Work"
Der Ring des Nibelungen, WWV 86 - is a "Collection Work"
Götterdämmerung, WWV 86D is a “member of” Der Ring des Nibelungen, WWV 86
The Well-Tempered Clavier, Book I - is a "Collection Work"
The Well-Tempered Clavier, Book I: Prelude and Fugue no. 2 in C minor, BWV 847 - is a "Top Level Work"
The Well-Tempered Clavier, Book I: Prelude and Fugue no. 2 in C minor, BWV 847 is a “member of” The Well-Tempered Clavier, Book I
Implementation thoughts:
“Class of Work” should be a new attribute of a work
"Part of" and “Member of” should be separately named relations - (in some senses belt and braces, but it reinforces the structure)
The current MB Series might be used for “Collection Works”