Check if a relationship of a given TYPE exists between two nodes.

[Kamesh Marellapudi]

Hi Guys, 

     I am new to Neo4j and am trying to get my feet wet here. Wondering if there is an existing API to evaluate if there is a relationship between two nodes of the given TYPE. For example A & B nodes have a relationship of TYPE,  'FRIENDS'. 

I did see some posts where they are trying to achieve this with relationship index but that solution is for finding a relationship between two nodes with the given property (key of the "key/value" pair) but relationship type is not modeled as a property on the relationship, right? Nor I would prefer to duplicate the relationship type as a property on the relationship either. I don't think looping through all the relationships between two nodes is an efficient solution either. 

Thanks in advance,

Kamesh

[Peter Neubauer]

Kamesh,
how many rels are attached to the nodes you are searching between, and
are these symmetric on both nodes?

Cheers,

/peter neubauer

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[Kamesh Marellapudi]

There could be more than one relationship between these nodes but not many. The relationship is uni-directional.

Thanks

Kamesh

[Peter Neubauer]

Then,
I would just do a little utility function

isRelated(Node a, Node b, RelationshipType type) {
rels = a.getRelationships();
for(Relationships r : rels) {
if (r.getType().equals(type){
return true;
}
}
return false;

}

This is NOT compiling :)

Cheers,

/peter neubauer

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On Mon, Mar 12, 2012 at 10:37 PM, Kamesh Marellapudi

[Michael Hunger]

And of course Peter missed the check :)

> public boolean isRelated(Node a, Node b, RelationshipType type) {
> for(Relationship r :a.getRelationships(type)) {
> if (r.getOtherNode(a).equals(b)) return true;
> }
> return false;

[Peter Neubauer]

We can have a java phone coding contest with the source code branched in mail threads. GIT and CI is for wimps.