Neo4J create temp variable within Cypher

Question

So my Top-Level problem is I am trying to return whether a MERGE resulted in the creation of a new Node or not.

In order to do this I was thinking I cou

Answer 1

You can do what you want, here's how (combination of my first answer, with @cybersam's addition). You just do it with a node property you create and then remove, instead of an unbound variable as you've been trying.

MERGE(tom:Person {id:'Tom Jones'})
ON CREATE set tom.temp_bool = true
ON MATCH set tom.temp_bool = false
WITH tom, tom.temp_bool AS result
REMOVE tom.temp_bool
RETURN result;

Answer 2

In simple merging cases like this where maximum one node could be created, a cleaner way to achieve what you are looking for could be checking the result stats. I case of using Bolt API you should check:

results.consume().counters.nodes_created = 1