 	r.vocabulary_id_1,
 	r.vocabulary_id_2,
 	r.relationship_id,
-	r.valid_start_date,
-	r.valid_end_date,
+    case when
+r.valid_start_date is null then (select latest_update from vocabulary WHERE vocabulary_id = 'HemOnc') else r.valid_start_date end,
+   case when
+r.valid_end_date is null then TO_DATE('20991231', 'yyyymmdd') else r.valid_end_date end,
 	r.invalid_reason
 FROM sources.hemonc_crs r
 JOIN concept_stage cs ON cs.concept_code = r.concept_code_1

	AND crs.relationship_id = 'Concept replaced by'
	AND crs.invalid_reason IS NULL;

-- At the end, the three tables concept_stage, concept_relationship_stage and concept_synonym_stage should be ready to be fed into the generic_update.sql script
				'Brand Name',
				'Component Class',
				'Route',
				'Regimen Class'
				)
			THEN 'Drug'
		WHEN h.concept_class_id IN (
				'Condition'
				)
			THEN 'Condition'
		WHEN h.concept_class_id IN (
