Multiple relationships between two nodes all become duplicates

relationship
(Davidgordonca) #1

First, I create multiple relationships between pairs of nodes to represent the jobs a Director held at a Company. When I check for duplicate relationships, result is zero.

MATCH (a:Director)-[r]->(b:Company)
with a, b, type(r) as tr, properties(r) as pr, count(properties(r)) as cpr
where cpr>1 and b.fraud=true
return sum(cpr-1) as numDuplicateRelationships

Then, I traverse the graph to set properties on Directors and Companies. When I check again for duplicate relationships, all pairs of nodes that have more than one relationship are now all duplicates. In other words, if a pair of nodes had 3 relationships, there are now 3 identical relationships.

I am at a loss why initially different relationships all become identical!

=====
Neo4j Browser version: 3.1.14
Neo4j Server version: [3.4.1] (community)
Traversing using cypher http endpoint
Checking duplicates with cypher browser

debug.log

[...]
2019-03-26 06:21:17.036+0000 INFO [o.n.k.i.s.c.CountsTracker] Rotated counts store at transaction 2607741 to [/var/lib/neo4j/data/databases/graph.db/neostore.counts.db.b], from [/var/lib/neo4j/data/databases/graph.db/neostore.counts.db.a].
2019-03-26 06:21:17.044+0000 INFO [o.n.k.i.t.l.c.CheckPointerImpl] Checkpoint triggered by scheduler for tx count threshold @ txId: 2607741 checkpoint completed in 19ms
2019-03-26 06:21:17.044+0000 INFO [o.n.k.i.t.l.p.LogPruningImpl] Pruned log versions 21446-21446, last checkpoint was made in version 21448
2019-03-26 06:21:27.044+0000 INFO [o.n.k.i.t.l.c.CheckPointerImpl] Checkpoint triggered by scheduler for tx count threshold @ txId: 2607744 checkpoint started...
2019-03-26 06:21:27.057+0000 INFO [o.n.k.i.s.c.CountsTracker] Rotated counts store at transaction 2607744 to [/var/lib/neo4j/data/databases/graph.db/neostore.counts.db.a], from [/var/lib/neo4j/data/databases/graph.db/neostore.counts.db.b].

0 Likes

(Elaine Rosenberg) #2

Can you show the code you use to traverse and set the properties?

0 Likes

(Davidgordonca) #3

Actually I believe this is being caused by py2neo OGM which does not support multiple relationships of the same type between a pair of nodes.

I thought that dropping down to cypher for relationship creation and then back to py2neo would be fine. Somehow, py2neo is defaulting the relationships to a single value.

I will test this tonight and report back

David

0 Likes

(Davidgordonca) #4

I was indeed correct in my assumption, namely that using py2neo caused the relationships between a pair of nodes to reset to the same value. Once I used cypher to traverse the graph and set various properties, the original multiple relationships remained the same.

Thanks for your quick reply, @elaine.rosenberg

0 Likes