EDIT

... hmm, maybe an even better solution is to show the field only if data exists. Is this possible?

Andreas Müller wrote:

... hmm, maybe an even better solution is to show the field only if data exists. Is this possible?

If we do so, we could also make all other fields invisible as they are alternative fields (either .. or ..) or implement #8778

Query to find example:

SELECT *
FROM OriginalSourceBase osb INNER JOIN DescriptionElementBase deb ON deb.id = osb.id
WHERE osb.cdmSource_id IS NOT NULL;

SELECT osb.id, osb.cdmSource_id, db.titleCache
FROM OriginalSourceBase osb INNER JOIN DescriptionBase_OriginalSourceBase MN ON MN.sources_id = osb.id
INNER JOIN DescriptionBase db ON db.id = MN.DescriptionBase_id 
WHERE osb.cdmSource_id IS NOT NULL;

e.g. Nepenthes morganiana in rem_conf_am