Neo4jClient C# How to get all nodes

Question

I am using Neo4jClient and Neo4j graph database in C# and I am wondering how I can retrieve all nodes with Neo4jClient.

Here is the cypher query to retrieve all nodes which have a relationship to "KNOWS" independently of the relationship direction :

start n =node(*) match n-[r:KNOWS]-(friend) return friend;

And here is the C# code with Neo4jClient :

var client = new GraphClient(new Uri("http://localhost:7474/db/data"));
client.Connect();

var cypherFluentQueryReturned = client.RootNode
                .StartCypher("n")
                .Match("n-[:KNOWS]->friend")
                .Return<Node<Person>>("friend");

However Neo4jClient doesn't allow to retrieve all nodes from * but only from a start point, here the root node.
How can I say with Neo4jClient to retrieve all nodes and not only nodes attached to root node?

It seems there is no way to query nodes from * through Neo4jClient.GraphClient.

However I can do that by executing a query with RawGraphClient :

CypherQuery query = new CypherQuery("start n=node(*) match n-[KNOWS]-(person) return person", new Dictionary<string, object>(), CypherResultMode.Set);
var persons = ((IRawGraphClient)client).ExecuteGetCypherResults<Person>(query).ToList();

Since Neo4JClient uses Neo4J's REST client, the JSON response for returning all nodes in a database could be quite large. This could be one of the reasons that it has not been implemented officially yet. If you are simply trying to query all nodes which have a relationship to "KNOWS", perhaps using indexes on relationships is something you could try. — Cameron Tinker

Tatham Oddie Tatham Oddie · Accepted Answer · 2013-03-22T04:41:15

Using Node<T>.StartCypher(identity) is a shortcut to both create a query and start it all in one go.

Instead, just create your query straight from the client:

client
    .Cypher
    .Start(new { n = All.Nodes })
    .Return<object>("n")

Then, you have full control over the START clause.

Neo4jClient C# How to get all nodes

2 Answers