olemus
atribuut, millel on olemi ühe isendi puhul mitu väärtust
= an attribute with multiple values for a single entity instance

ülevaateid
https://www.quora.com/What-are-multivalued-attributes-and-how-can-they-be-handled-within-the-database-design

https://techdocs.broadcom.com/us/en/ca-mainframe-software/devops/ca-gen/8-6/developing/analyzing/analyzing-data/composite-and-multi-valued-attributes.html