So far, there is no node exists cypher statement in Neo4j. At some scenario, you might want to test if a with specific property exists or not. In this case, here is the cypher statement can be used to verify is a node exist:
OPTIONAL MATCH (n:Person {name: 'Tom Hanks'})
RETURN n IS NOT NULL AS Predicate
So why are we using OPTIONAL MATCH , what does OPTIONAL MATCH means?
OPTIONAL MATCH matches patterns against your AuraDB Instance, just like MATCH does. The difference is that if no matches are found, OPTIONAL MATCH will use a null for missing parts of the pattern. OPTIONAL MATCH could be considered the Cypher equivalent of the outer join in SQL.
OPTIONAL MATCH (p:Person {id:123})
WITH p
RETURN p.name
ref: https://neo4j.com/docs/cypher-manual/current/clauses/optional-match/
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