Issue with graph depth

[Deimrus]

Hey all.
I have a simple structure:

Cypher query in Browser works as expected but the same query in @query directive within Neo4jRepository returns just one random underlying node of label ObjectType so instead of getting one Company with two Sites with two ObjectTypes for each Site I got just one ObjectType:

Neo4jClient returns all the data I need btw.

Is this a bug or I do something wrong?

[Deimrus]

Screenshots made on Spring Boot version 3.0.1 and related version of spring-boot-starter-data-neo4j. Also checked it on 2.7.* and 2.6.* with the same results.

[meistermeier]

To investigate this, I would need the domain model for the three classes in question.
It should work with repositories. The Neo4jClient presents the correct data because it does not inspect the mappings but returns the values from the database before mapping.

[Deimrus]

@Node
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Company {
    @Id @GeneratedValue
    private Long id;
    private String name;
    @Relationship(type = "IS_IN", direction = Relationship.Direction.INCOMING)
    private Set<Site> sites = new HashSet<>();
}

@Node
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Site {
    @Id @GeneratedValue
    private Long id;
    private Integer name;
    @Relationship(type = "IS_IN", direction = Relationship.Direction.INCOMING)
    private Set<ObjectType> types = new HashSet<>();
}

@Node
@Data
@AllArgsConstructor
@NoArgsConstructor
public class ObjectType {
    @Id @GeneratedValue
    private Long id;
    private String name;
}

[Deimrus]

Also List<Company> findAll(); method without @query returns all the data as expected but with warnings:

MATCH (company:`Company`) RETURN company{.id, .name, __nodeLabels__: labels(company), __internalNeo4jId__: id(company), __elementId__: toString(id(company)), Company_IS_IN_Site: [(company)<-[:`IS_IN`]-(company_sites:`Site`) | company_sites{.id, .name, __nodeLabels__: labels(company_sites), __internalNeo4jId__: id(company_sites), __elementId__: toString(id(company_sites)), Site_IS_IN_ObjectType: [(company_sites)<-[:`IS_IN`]-(company_sites_types:`ObjectType`) | company_sites_types{.id, .name, __nodeLabels__: labels(company_sites_types), __internalNeo4jId__: id(company_sites_types), __elementId__: toString(id(company_sites_types))}]}]}
  WARN 22120 --- [nio-8080-exec-1] org.springframework.data.neo4j.cypher    : Neo.ClientNotification.Statement.UnknownPropertyKeyWarning: The provided property key is not in the database
	MATCH (company:`Company`) RETURN company{.id, .name, __nodeLabels__: labels(company), __internalNeo4jId__: id(company), __elementId__: toString(id(company)), Company_IS_IN_Site: [(company)<-[:`IS_IN`]-(company_sites:`Site`) | company_sites{.id, .name, __nodeLabels__: labels(company_sites), __internalNeo4jId__: id(company_sites), __elementId__: toString(id(company_sites)), Site_IS_IN_ObjectType: [(company_sites)<-[:`IS_IN`]-(company_sites_types:`ObjectType`) | company_sites_types{.id, .name, __nodeLabels__: labels(company_sites_types), __internalNeo4jId__: id(company_sites_types), __elementId__: toString(id(company_sites_types))}]}]}
	                                          ^
One of the property names in your query is not available in the database, make sure you didn't misspell it or that the label is available when you run this statement in your application (the missing property name is: id)
  WARN 22120 --- [nio-8080-exec-1] org.springframework.data.neo4j.cypher    : Neo.ClientNotification.Statement.UnknownPropertyKeyWarning: The provided property key is not in the database
	MATCH (company:`Company`) RETURN company{.id, .name, __nodeLabels__: labels(company), __internalNeo4jId__: id(company), __elementId__: toString(id(company)), Company_IS_IN_Site: [(company)<-[:`IS_IN`]-(company_sites:`Site`) | company_sites{.id, .name, __nodeLabels__: labels(company_sites), __internalNeo4jId__: id(company_sites), __elementId__: toString(id(company_sites)), Site_IS_IN_ObjectType: [(company_sites)<-[:`IS_IN`]-(company_sites_types:`ObjectType`) | company_sites_types{.id, .name, __nodeLabels__: labels(company_sites_types), __internalNeo4jId__: id(company_sites_types), __elementId__: toString(id(company_sites_types))}]}]}
	                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     ^
One of the property names in your query is not available in the database, make sure you didn't misspell it or that the label is available when you run this statement in your application (the missing property name is: id)
  WARN 22120 --- [nio-8080-exec-1] org.springframework.data.neo4j.cypher    : Neo.ClientNotification.Statement.UnknownPropertyKeyWarning: The provided property key is not in the database
	MATCH (company:`Company`) RETURN company{.id, .name, __nodeLabels__: labels(company), __internalNeo4jId__: id(company), __elementId__: toString(id(company)), Company_IS_IN_Site: [(company)<-[:`IS_IN`]-(company_sites:`Site`) | company_sites{.id, .name, __nodeLabels__: labels(company_sites), __internalNeo4jId__: id(company_sites), __elementId__: toString(id(company_sites)), Site_IS_IN_ObjectType: [(company_sites)<-[:`IS_IN`]-(company_sites_types:`ObjectType`) | company_sites_types{.id, .name, __nodeLabels__: labels(company_sites_types), __internalNeo4jId__: id(company_sites_types), __elementId__: toString(id(company_sites_types))}]}]}
	                                                                                                                                                                                                                                                 ^
One of the property names in your query is not available in the database, make sure you didn't misspell it or that the label is available when you run this statement in your application (the missing property name is: id)

[meistermeier]

The custom query will return multiple records not just "one path". Every branch will create an entry.
But since SDN uses a record-centric mapping to insure e.g. immutable mapping and reactive streaming, you need to aggregate the result on the database side.
Even though it looks a little bit complex, this is exactly what you want to have:

MATCH res = (c:Company)<--(:Site)--()
 WITH collect(res) as paths, c
 WITH c,
 reduce(a=[], node in reduce(b=[], c in [aa in paths | nodes(aa)] | b + c) | case when node in a then a else a + node end) as nodes,
 reduce(d=[], relationship in reduce(e=[], f in [dd in paths | relationships(dd)] | e + f) | case when relationship in d then d else d + relationship end) as relationships
 RETURN c, relationships, nodes;

It reduces all nodes and relationships into a single record to be returned.
More about this here:
https://docs.spring.io/spring-data/neo4j/docs/current/reference/html/#custom-queries.for-relationships.long-paths.database

For the warning, I just commented here how to mitigate this in your application config: #2660 (comment)

[Deimrus]

Yep, result tree as it should be. I think I got the point.

Thank you for help.