Could not fetch author data: null value in column "affiliation_country" of relation "journals_cachedauthor" violates not-null constraint DETAIL: Failing row contains (d9a71033-9cbc-46f7-8fa3-b263cfc99817, A5075988802, Stefan Chmiela, Berlin Institute for the Foundations of Learning and Data, 52, 5616, 0000-0003-0892-952X, 2026-04-29 11:06:09.044854+00, 2026-04-29 11:06:09.045007+00, null, 17, 19, , ["Machine Learning in Materials Science", "Protein Structure and..., stefan-chmiela).