--- a/OrthancServer/ServerEnumerations.cpp	Tue Oct 20 10:24:10 2015 +0200
+++ b/OrthancServer/ServerEnumerations.cpp	Tue Oct 20 10:39:21 2015 +0200
@@ -365,4 +365,25 @@
     }
   }
 
+
+  DicomTag GetIdentifierTag(ResourceType level)
+  {
+    switch (level)
+    {
+      case ResourceType_Patient:
+        return DICOM_TAG_PATIENT_ID;
+
+      case ResourceType_Study:
+        return DICOM_TAG_STUDY_INSTANCE_UID;
+        
+      case ResourceType_Series:
+        return DICOM_TAG_SERIES_INSTANCE_UID;
+        
+      case ResourceType_Instance:
+        return DICOM_TAG_SOP_INSTANCE_UID;
+
+      default:
+        throw OrthancException(ErrorCode_ParameterOutOfRange);
+    }
+  }
 }