Add multiple relations to centers & research fields & publishers for publications in the extraction module

Add multiple relations to centers & research fields & publishers for publications in the extraction module.

This involves:

• when a publication PID (DOI) is found for multiple centers, to add multiple relations in the table center_has_publication. Conflict management (will be iteratively updated): See below.
• when a publication PID (DOI) is found for multiple centers but with different research fields and/or subfields, to add multiple relations in the tables research_field_has_publication and/or research_sub_field_has_publication
• when multiple publisher names are found for a publication, to add multiple relations in a new table publisher_has_publication (while migrating from the current procedure where values are added to a list)

Please note, that these database updates for v2.1 need to be kept separated from those databases accessed by the dashboard v 2.0 (production and test servers)

Update 2024/09/30

Conflict management: If a publication PID (DOI) is found for multiple centers, multiple relations are added to the table "center_has_publication".

• We will only update the reference tables "center_has_publication", "research_field_has_publication", "research_subfield_has_publication", (as harvested from the centers' OAI-PMH interfaces).
• For now, we do not update any bibliographic metadata in the metada fields of a database entry for a publication (type, title, journal, year, ids, last_updated, publicatioon_date, publication_authors).
• As "publisher_has_publication" is filled from Scholix metadata, this does not have to be updated.

Update 2024/11/25

• ✅ Successful tests of adding multiple centers
• ✅ Successful tests of adding multiple research fields
• Still problems with multiple entities of research-subfields 🚧