Incremental-Load.md

@@ -67,6 +67,16 @@ When a Encounter/Procedure/Observation/MedicationAdministration/Condition resour
 
 Due to the fact that the resource types are read in random order, it may happen that the referenced Patient resource and Encounter resource is not yet available in OMOP CDM. In this case, a dummy for the Patient resource and a dummy for the Encounter resource is created and written to OMOP CDM. If the "real" Patient resource and Encounter resource is to be written to OMOP CDM during incremental loading, only an update of the dummies takes place.
 
+Next the job checks if the read resource (e.g. Condition) already exists in OMOP CDM. This is done in the following tables using specific columns:
+
+**Encounter resource**
+* table: VISIT_DETAIL
+* columns: person_id, procedure_concept_id, procedure_datetime, procedure_source_concept_id
+
+**Procedure resource**
+* table: PROCEDURE_OCCURRENCE
+* columns: person_id, visit_detail_start_datetime, visit_occurrence_id
+
 ![inkrementellesLaden-Others](uploads/9c72e7aa867269a57cce9e9bc74495de/inkrementellesLaden-Others.png)
 
 </details>