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neo4jcypherpy2neo

How do I count all the other nodes related to a specific node

The path is representing for users' browse history.

The upper path means there's one user who has browsed page A -> page B -> page C

The lower path means, one user browsed page X-> page Y -> page B -> page C

For example, If I want to calculate the relevance with page C

The expected anwser is on the table

Or if I want to find all the relevance with page B

the anwser should be

  • page A : 1
  • page X : 1
  • page Y : 1
  • page C : 0

How could I get the expected anwser with py2neo or cypher query

Solution

  • If your "b" nodes are different nodes, and thus you have complete distinct paths, this query works :

    MATCH (b:Page)
WHERE b.id = 'b'
MATCH (b)<-[:LINK_TO*..10]-(referer)
RETURN referer.id, count(*)

    Result : 

    y   1
a   1
x   1

    Test console here http://console.neo4j.org/r/sb5qmq

    Change 'b' by c to see that b will have a count of 2

    b   2
y   1
a   1
x   1

    EDIT

    If your nodes 'b' are the same, you can do this :

    MATCH (b:Page { id:'b' })
WITH b
MATCH (p:Page)
WHERE p <> b
OPTIONAL MATCH (p)-[r:LINK_TO*..3]->(b)
RETURN p.id, count(r)

    http://console.neo4j.org/r/prb2my