As a repository manager, I want only one heading (e.g. agent, subject, classification) of certain type/form to be linked to a material description context record (e.g., accession, resource, digital object)
Currently, the same heading (e.g., agent name, role, and relator / subject term / classification term) can be linked multiple times to the same material description parent or component record. There is no benefit it doing this and allowing it leads to potential cleanup of the ASpace records and/or the exports.
It would be best to put in place a uniqueness constraint that allows only one heading of a certain form to be linked to a material description context record. This uniqueness constraint will need to take into account the different values that can be present in a linked heading record, e.g., agent name, role, and relator for linked agent records, subject term and sub-terms (including syntax) for linked subject records, and classification terms and ids for linked classification records.
To give an example of the problem, Classification A is already linked to Resource B. There is no constraint on Classification A being linked to Resource B a second time, even though this serves no purpose. The new duplicate linkage is created in the database, but does not impact the staff or public interfaces.
This ticket was discussed at the October 7, 2019 meeting of Dev. Pri. We decided to:
Reduce the priority to minor, as (to our knowledge) this problem does not currently cause any problems in use of ArchivesSpace. Nevertheless, it is a concern due to the potential for confusion and database bloat.
Request clarification from the submitter or other interested parties on the recommended method for introducing a uniqueness constraint without causing issues with legacy data.