CONSTRAINT CONFERENCE_FK2 FOREIGN KEY(ROOMNO) REFERENCES ROOM(ROOMNO) :Ein Fremdschlüssel muss das Gesamt referenzieren Primärschlüssel (oder eindeutiger Schlüssel) einer anderen Tabelle. Fügen Sie also einfach buildingno:
CONSTRAINT CONFERENCE_FK2 FOREIGN KEY(BUILDINGNO, ROOMNO) REFERENCES ROOM(BUILDINGNO, ROOMNO)
