A successful mapping is created when the user "drops" the dragged attribute onto a valid entity attribute. A mapping line is then displayed joining the source attribute from the datastore entity to the target attribute on the evidence entity. A line is also displayed between the title bars of the entities themselves to indicate that the mapping link is also between the entities and not just the specific entity attributes. When subsequent mappings are created between attributes, lines are only drawn between these mapped attributes because the entity mapping line already exists.