When using MERGE on full patterns, the behavior is that either the whole pattern matches, or the whole pattern is created. MERGE will not partially use existing patterns — it’s all or nothing. If partial matches are needed, this can be accomplished by splitting a pattern up into multiple MERGE clauses. http://docs.neo4j.org/chunked/stable/query-merge.html MERGE (n)-[:know {r:’123′}]->(test2 {name:’2′}) will … Read more
I am not sure I fully understand the problem. But as I read it: You have no problems connecting to Neo4J or handling any of the Neo4J-specific elements. You are not able to properly manage multiple partitions; there is no persistency or means to ensure that communication across partitions is correct. If my understanding is … Read more
Yes, you can do something like: match (gal:Person{name:”Yoav”})-[:liked|:watched|:other]->(movie:Movie) return movie Take a look in the docs: Match on multiple relationship types EDIT: From the comments: I need “and” between the relation types.. you gave me an “or” In this case, you can do: match (Yoav:Person{name:”Yoav”})-[:liked]->(movie:Movie), (Yoav)-[:watched]->(movie), (Yoav)-[:other]->(movie) return movie
No, there isn’t. All relationships in neo4j have a direction, starting and ending at a given node. There are a small number of workarounds. Firstly, as you’ve suggested, we can either have two relationships, one going from A to B and the other from B to A. Alternatively, when writing our MATCH query, we can … Read more
You can use the browser instead of the API. Just go to http://localhost:7474 (or whatever IP to which the web console is bound) and you will be prompted to change the password. Once authenticated, use the command :server change-password to change the password again. It is not yet possible to create multiple user accounts within … Read more
As Michael Hunger mentioned MATCH (n) WHERE NOT EXISTS(n.foo) RETURN n On older versions of Neo4j you can use HAS: # Causes error with later versions of Neo4j MATCH (n) WHERE NOT HAS(n.foo) RETURN n
The easiest is to start the neo4j server and view your graph via the webadmin: http://docs.neo4j.org/chunked/stable/tools-webadmin.html
You first need confirm that the database you are connecting to was properly shut down (means you should not take the image of a running database). Set the location of the database if you are in server mode from the file conf/neo4j-server.properties by editing the below line. org.neo4j.server.database.location=data/graph.db if you are using embedded neo4j you … Read more
I’m sorry you can’t reproduce the results. However, on a MacBook Air (1.8 GHz i7, 4 GB RAM) with a 2 GB heap, GCR cache, but no warming of caches, and no other tuning, with a similarly sized dataset (1 million users, 50 friends per person), I repeatedly get approx 900 ms using the Traversal … Read more
There is a difference: comma separated matches are actually considered part of the same pattern. So for instance the guarantee that each relationship appears only once in resulting path is upheld here. Separate MATCHes are separate operations whose paths don’t form a single patterns and which don’t have these guarantees.