问题
I have the following query that uses plain relationship operations for node filtering:
MATCH (dg:DecisionGroup)-[:CONTAINS]->(childD:Decision)
WHERE dg.id = 1
MATCH (childD)-[relationshipValueRel2:HAS_VALUE_ON]->(filterCharacteristic2:Characteristic)
WHERE filterCharacteristic2.id = 2
WITH relationshipValueRel2, childD, dg
WHERE (ANY (id IN [".NET"] WHERE id IN relationshipValueRel2.value ))
RETURN childD.name
which returns only one node(as it was expected):
"Candidate1"
PROFILE output:
I'd like to optimize the query performance and this is why I use the following trigger in order to add the relationship into the manual index:
CALL apoc.trigger.add('HAS_VALUE_ON_ASSIGNED_RELATIONSHIP_PROPERTIES_TRIGGER', "UNWIND keys({assignedRelationshipProperties}) AS key
UNWIND {assignedRelationshipProperties}[key] AS map
WITH map
WHERE type(map.relationship) = 'HAS_VALUE_ON'
CALL apoc.index.addRelationship(map.relationship, keys(map.relationship)) RETURN true",
{phase:'before'})
and the following query in order to get the same data as the first one but only from the manual index:
MATCH (dg:DecisionGroup)-[:CONTAINS]->(childD:Decision)
WHERE dg.id = 1
MATCH (childD)-[relationshipValueRel2:HAS_VALUE_ON]->(filterCharacteristic2:Characteristic)
WHERE filterCharacteristic2.id = 2
WITH relationshipValueRel2, filterCharacteristic2, childD, dg
CALL apoc.index.in(filterCharacteristic2,'HAS_VALUE_ON','(value:(".NET"))')
YIELD node WITH node AS childD
RETURN childD.name
but the issue is, that this query returns two instances of the same node:
"Candidate1"
"Candidate1"
PROFILE output:
What am I doing wrong and why this query returns 2 instances instead of the single one ?
来源：https://stackoverflow.com/questions/50493806/neo4j-cypher-manual-relationship-index-apoc-trigger-and-data-duplication