GDS on filtered graph data?

[aiden-huffman]

Describe the bug Filtering before gds.graph.project doesn't work as expected

To Reproduce

CREATE (a:Location {name: 'A'}),
       (b:Location {name: 'B'}),
       (c:Location {name: 'C'}),
       (d:Location {name: 'D'}),
       (e:Location {name: 'E'}),
       (f:Location {name: 'F'}),
       (a)-[:ROAD {cost: 50, construction: True}]->(b),
       (a)-[:ROAD {cost: 50, construction: False}]->(c),
       (a)-[:ROAD {cost: 100, construction: False}]->(d),
       (b)-[:ROAD {cost: 40, construction: False}]->(d),
       (c)-[:ROAD {cost: 40, construction: False}]->(d),
       (c)-[:ROAD {cost: 80, construction: False}]->(e),
       (d)-[:ROAD {cost: 30, construction: False}]->(e),
       (d)-[:ROAD {cost: 80, construction: False}]->(f),
       (e)-[:ROAD {cost: 40, construction: False}]->(f);

We would like to avoid roads with construction when calculating shortest paths.

MATCH (a)-[e]->(b)
WHERE e.cost IS NOT NULL AND NOT e.construction
RETURN a, e, b

Despite the table not containing the edge with construction, the Graph visualisation does.

MATCH (a)-[e]->(b)
WHERE e.cost IS NOT NULL AND NOT e.construction
WITH gds.graph.project(
    'filteredGraph',
    a, b,
    {relationshipProperties: {cost: e.cost}}) AS g
RETURN g.graphName

The GDS projection also keeps the edge and will return the same result as the example here

GDS version: X.Y.Z Neo4j version: 5.11.0 Operating system: (Ubuntu 22.04)

Expected behavior Expect a projection of the filtered graph data, and the resulting calculation to be performed there.

[FlorentinD]

Hello, Thank you for the bug report! However, I am failing to reproduce your problem completly. The input graph consists of 6 nodes and 9 relationships.

First when visualizing the filted query in Neo4j browser, I could reproduce the issue. This is due to the Connect result nodes setting, which you want to uncheck in your case (https://neo4j.com/docs/browser-manual/current/operations/browser-settings/).

However, with your project query, the projected graph inside GDS correctly filters out the one relationship and results in 6 nodes and 8 relationships. You can also check with gds.graph.degree.stream('filteredGraph'). For the example you linked, could you clarify what you executed to verify your result?

[aiden-huffman]

Seems there was something wrong in the database on my end. We recently reset the database to reinitialize everything and the issue appears to be resolved. Thank you for taking a look.