How to set weights for infered edges?

Neo4j Graph Platform Cypher
1

I would like to add edges between nodes of distance 2 apart, and set a weight property according to how many such paths of length 2 exists. I think a query like this is close, but isn't quite right:

Match path=((u1:User)-[:KNOWS]->(:User)-[:KNOWS]->(u2:User))
With u1, u2, Count(path) as weight
Merge (u1)-[e:FILLEDIN]->(u2)
Set e.weight=weight

This doesn't seem to do anything in my graph. What's the best way to do this?

2

That looks fine to me. You may want to check that you're using the right labels. If you stopped your query early, doing a RETURN on line 2 instead of a WITH, do you get results back?

3

Ah, you're right! There was a typo in my labels, thank you.

Related to my question: is it possible to return a "view" of the resulting edges in the browser without actually saving the new edges to the database?

4

Hi Rogie,

The view you are looking for might be a good use case for virtual relationships with the apoc library. 14.2. Virtual Nodes/Rels - Chapter 14. Virtual Nodes & Relationships (Graph Projections)

Match path=((u1:User)-[:KNOWS]->(:User)-[:KNOWS]->(u2:User))
With u1, u2, Count(path) as weight
RETURN u1, u2, apoc.create.vRelationship(u1,'FILLEDIN',{weight:weight},u2) as rel;

Best wishes,
Nathan

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