Pascal Ehlers
--- a/toolbox/data_enricher/metadata_extractor/dublin_core_xml_metadata_extractor.py
+++ b/toolbox/data_enricher/metadata_extractor/dublin_core_xml_metadata_extractor.py
-                    oai_identifier,
-                    research_fields,
-                )
+            research_fields = get_mapped_research_fields(self._get_specs(xml)) or []

            # we don't want to pick "other" or "unknown" if it exists here
            research_fields = [
                rf for rf in research_fields if rf not in ["Other", "Unknown"]
            ]

-            return research_fields[0] if research_fields else None
+            return research_fields

        if center == "GFZ" and pub_year and int(pub_year) >= 2021:
-            return "Earth and Environment"
+            return ["Earth and Environment"]
--- a/toolbox/exporter/db_models/LitPub/lit_pub_insert.py
+++ b/toolbox/exporter/db_models/LitPub/lit_pub_insert.py
        name=center,
        cursor=cursor,
    )
-
    cursor.execute(
        """
-        INSERT INTO center_has_publication
+        INSERT IGNORE INTO center_has_publication
--- a/toolbox/exporter/db_models/LitPub/lit_pub_insert.py
+++ b/toolbox/exporter/db_models/LitPub/lit_pub_insert.py
+    Function for update class so that _has_ tables get updates even if the publication is already inserted
+    into database
+    """
+
+    if lit_pub.LitHelmholtzCenter:
+        _insert_helmholtz_center(cursor, pid, lit_pub.LitHelmholtzCenter)
+
+    if lit_pub.HelmholtzResearchField:
+        _insert_research_field(cursor, pid, lit_pub.HelmholtzResearchField)
+
+    if lit_pub.HelmholtzResearchSubField:
+        _insert_research_sub_field(cursor, pid, lit_pub.HelmholtzResearchSubField)
+
+    if lit_pub.LitPublisher:
+        _insert_publication_has_publisher(cursor, pid, lit_pub.LitPublisher)
+
--- a/toolbox/type_definitions/lit_metadata_dict.py
+++ b/toolbox/type_definitions/lit_metadata_dict.py
    LitInternalID: Optional[str] = None
    LitInternalIDType: Optional[str] = None
    LitHelmholtzCenter: Optional[str] = None
-    HelmholtzResearchField: Optional[str] = None
-    HelmholtzResearchSubField: Optional[str] = None
+    HelmholtzResearchField: list[str] = []
+    HelmholtzResearchSubField: list[str] = []
    HelmholtzLargeScaleFacilities: list[str] = []
    HelmholtzInstruments: list[str] = []