Ndtyjky

I have an existing Neo4 query to bring back user interests and if any of those interests are related. The query is:

MATCH (u:User)-[r1:INTERESTED_IN]-(i1:Interest)

WHERE u.emailAddress = 'bob@mail.com'

OPTIONAL MATCH (u)-[r2:INTERESTED_IN]-(i2:Interest)

OPTIONAL MATCH (i1)-[r3:RELATED_TO]-(i2)

RETURN u, r1, i1, r2, i2, r3

This maps to a Spring Data Neo4J repository method as:

User findInterestsByEmailAddressIgnoreCase(@Param("emailAddress") String emailAddress);

I want to extend the graph so that users can know other users (e.g. bob knows fred and tom and fred and tom know each other too). How do I modify the same query to also bring back these relationships?

I tried adding an optional match for a user knowing another user as follows:

MATCH (u:User)-[r1:INTERESTED_IN]-(i1:Interest)

WHERE u.emailAddress = 'bob@mail.com'

OPTIONAL MATCH (u)-[r2:INTERESTED_IN]-(i2:Interest)

OPTIONAL MATCH (i1)-[r3:RELATED_TO]-(i2)

OPTIONAL MATCH (u:User)-[r5:KNOWS]-(u2:User)

RETURN u, r1, i1, r2, i2, r3, r5, u2

This seems to run and bring back the graph in the neo4j browser but Spring Data seems to fail with the error

org.springframework.dao.IncorrectResultSizeDataAccessException:
Incorrect result size: expected at most 1
at org.springframework.data.neo4j.repository.query.GraphQueryExecution$SingleEntityExecution.execute(GraphQueryExecution.java:83)

Any pointers on what I need to change in the query?

Updates

1. 
   

   User class

   
   
   

   @NodeEntity
   
   public class User {
   
   
   
   @Id
   
   @GeneratedValue
   
   private Long id;
   
   
   
   public Long getId() {
   
       return id;
   
   }
   
   
   
   @Index(unique = true)
   
   private String emailAddress;
   
   
   
   private String name;
   
   
   
   @Relationship(type = "INTERESTED_IN", direction = Relationship.OUTGOING)
   
   private Set<UserInterest> interests = new HashSet<>();
   
   
   
   public Set<UserInterest> getInterests() {
   
       return interests;
   
   }
   
   
   
   public void setInterests(Set<UserInterest> interests) {
   
       this.interests = interests;
   
   }
   
   
   
   @Relationship(type = "KNOWS", direction = Relationship.UNDIRECTED)
   
   private Set<RelatedUser> relatedUsers = new HashSet<>();
   
   
   
   public Set<RelatedUser> getRelatedUsers() {
   
       return relatedUsers;
   
   }
   
   
   
   public void setRelatedUsers(Set<RelatedUser> relatedUsers) {
   
       this.relatedUsers = relatedUsers;
   
   }
   
   
   
   ... additional getters/setters
   
   
   
   }
   
   

   
   

According to the Spring-data-neo4j docs, the proper method signature is

// <class> finedBy<property><flags>(<property type> value)

User findByEmailAddressIgnoreCase(String emailAddress)