Find path in Neo4j with directed edges

Question

This is my first attempt at Neo4j, please excuse me if I am missing something very trivial. Here is my problem:

Consider the graph as created in the following Neo4j console example: http://console.neo4j.org/?id=y13kbv

We have following nodes in this example:

(Person {memberId, memberName, membershipDate})

(Email {value, badFlag})

(AccountNumber {value, badFlag})

We could potentially have more nodes capturing features related to a Person like creditCard, billAddress, shipAddress, etc. All of these nodes will be the same as Email and AccountNumber nodes: (creditCard {value, badFlag}), (billAddress {value, badFlag}),etc.

With the graph populated as seen in the Neo4j console example, assume that we add one more Person to the graph as follows:

(p7:Person {memberId:'18' , memberName:'John', membershipDate:'12/2/2015'}),
(email6:Email {value: 'john@gmail.com', badFlag:'false'}),
(a2)-[b13:BELONGS_TO]->(p7),
(email6)-[b14:BELONGS_TO]->(p7)

When we add this new person to the system, the use case is that we have to check if there exists a path from features of the new Person ("email6" and "a2" nodes) to any other node in the system where the "badFlag=true", in this case node (a1 {value:1234, badFlag:true}).

Here, the resultant path would be (email6)-[BELONGS_TO]->(p7)<-[BELONGS_TO]-(a2)-[BELONGS_TO]->(p6)<-[BELONGS_TO]-(email5)-[BELONGS_TO]->(p5)<-[BELONGS_TO]-(a1:{badFlag:true})

I tried something like this:

MATCH (newEmail:Email{value:'john@gmail.com'})-[:BELONGS_TO]->(p7)-[*]-(badPerson)<-[:BELONGS_TO]-(badFeature{badFlag:'true'}) RETURN badPerson, badFeature;

which seems to work when there is only one level of chaining, but it doesn't work when the path could be longer like in the case of Neo4j console example.

I need help with the Cypher query that will help me solve this problem. I will eventually be doing this operation using Neo4j's Java API using my application. What could be the right way to go about doing this using Java API?

cybersam · Answer 1 · 2015-12-24T06:43:42.373

You had a typo in you query. PART_OF should be BELONGS_TO. This should work for you:

MATCH (newEmail:Email {value:'john@gmail.com'})-[:BELONGS_TO]->(p7)-[*]-(badPerson)<-[:BELONGS_TO]-(badFeature {badFlag:'true'})
RETURN badPerson, badFeature;

Aside: You seem to use string values for all properties. I'd replace the string values 'true' and 'false' with the boolean values true and false. Likewise, values that are always numeric should just use integer or float values.

Find path in Neo4j with directed edges

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