Basic Neo4j Cypher query to link all the individuals in the graph database using the same email address

personlinker.cypher

MATCH (a:Person), (b:Person {email:a.email})
WHERE HAS(a.email) AND HAS(b.email) 
AND a.email IS NOT NULL AND b.email IS NOT NULL
AND a<>b
CREATE UNIQUE (a)-[i:IS]-(b);