Head's Up! These forums are read-only. All users and content have migrated. Please join us at community.neo4j.com.
01-29-2021 08:00 AM
The scenario is as follows
User A-[follows]->B and B-[follows]-A
with such bidirectional relation between same Node entities, load cypher for A takes indefinite to load.
<MATCH (n:User
) WHERE n.id = $id WITH n, id(n) AS internalNeo4jId RETURN n{ .name, .passToken, .phoneNumber, nodeLabels: labels(n), internalNeo4jId: id(n), paths: [p = (n)-[:right_swiped
|Knows
|left_swiped
|part_of
]->()-[:right_swiped
|Knows
|left_swiped
|part_of
*0..]-()-[:right_swiped
|Knows
|left_swiped
|part_of
*0..]-()-[:right_swiped
|Knows
|left_swiped
|part_of
*0..]-() | p]}/>
This cypher is created by Spring Data neo4j but even if I copy-paste this to desktop neo4j, it times out.
My question is, does Neo4j support such relationship models? If yes than does Spring is creating the issue by creating a cypher which times out.
01-29-2021 08:39 AM
Do you really need an arbitrary length relationship? This fragment part_of *0..
will create a huge search space.
To see if this works at all, first try using no variable length, then a more modest variable length, e.g. part_of *1..3
I'm also not sure why you have 0
since a two nodes must have a minimum of 1 relationship.
01-29-2021 09:00 AM
Thanks, Clem
This cypher is created by Spring Data to fetch full Node.
I wanted to find out whether this is a Spring issue or Neo4j is not capable of handling such relation structures.
01-29-2021 09:05 AM
This is a problem that started coming with SDN 6. SDN 5 had @Depth annotation to limit the depth in the generated query.
I'm facing the issue and considering downgrading to SDN 5. See: java - How should one migrate from the removed @Depth annotation in Spring Data Neo4j 6? - Stack Ove...
My opinion is that it should be considered a bug in SDN where one issue is fixed but another opened. With this query, SDN attempts to load almost entire connected graph which is impractical and is not desired.
All the sessions of the conference are now available online