Stack Overflow
Stack Overflow

Questions tagged [neo4j]

Neo4j is an open-source graph database (GDB) well suited to connected data. Please mention your exact version of Neo4j when asking questions. You can use it for recommendation engines, fraud detection, graph-based search, network ops/security, and many other user cases. The database is accessed via official drivers in Java, JavaScript, Python and .NET, or community-contributed drivers in PHP, Ruby, R, Golang, Elixir, Swift and more.

Neo4j is a open-source, transactional, high-performance native graph database.

Neo4j stores its data as a graph: Nodes are connected through Relationships, both with arbitrary properties. Neo4j features a graph-centric declarative query language called Cypher. Its drivers support many programming languages. More details in the Online Training and the Neo4j Manual.

Neo4j offers a fully-managed cloud database (Database as a service) called Neo4j AuraDB.

For questions that are not suitable for the Stack Overflow Q&A Format, please reach out on Discord. Neo4j also maintains a public Feedback Board for feature ideas and future development directions.

Useful Links

External Resources

Related Tags

22696 questions
14
votes
2 answers

DETACH DELETE Neo4j 2.3.x/Cypher

What is the behaviour and purpose of the new Cypher operator DETACH DELETE added in Neo4j 2.3.x?
alexanoid
  • 24,051
  • 54
  • 210
  • 410
14
votes
2 answers

Cypher: Use UNWIND with potentially empty collection

Is there any way to use UNWIND for potentially empty collections (e.g. OPTIONAL UNWIND g)? For instance, in the attached query it occurs that the collection (items) is empty sometimes (3rd block), but the results of the other collections are still…
Sebastian Woinar
  • 440
  • 1
  • 8
  • 15
14
votes
1 answer

Neo4j - NOT IN query

The graph schema I have is (actors)-[:ACTED_IN]->(movies). I know how to find actors who have worked with a particular actor as below: MATCH (actor {name:"Tom Hanks"} )-[:ACTED_IN]->(movies)<-[:ACTED_IN]-(costars) return distinct costars; I know how…
Jack
  • 741
  • 1
  • 8
  • 25
14
votes
4 answers

Neo4J Cypher data type conversion

I've got a property quantity on our Product-nodes and am looking to do a cypher query that gives me all nodes with quantity = 20 ... problem is that quantity is stored as a string in neo4j. Is there a way to cast the property to integer in the…
ChrisR
  • 14,370
  • 16
  • 70
  • 107
14
votes
1 answer

What is the status on Neo4j's horizontal scalability project Rassilon?

Just wondering if anyone has any information on the status of project Rassilon, Neo4j's side project which focuses on improving horizontal scalability of Neo4j? It was first announced in January 2013 here. I'm particularly interested in knowing more…
Mike
  • 683
  • 10
  • 22
14
votes
2 answers

Detecting cycles in neo4j property graph using cypher

What is the best way to detect for cycles in a graph of a considerable size using cypher. I have a graph which has about 250000 nodes and about 270000 relationship and I would like to detect cycles in sub graph of about 10k nodes and involving 100k…
Amit
  • 435
  • 3
  • 13
14
votes
1 answer

Cypher query: Finding all paths between two nodes filtered by relationship properties

I have the following graph as a Neo4j graph database: activates (80 °F) (A)------------------------------------->(D) | \__ _/->^ | …
Orion
  • 1,104
  • 3
  • 16
  • 40
14
votes
1 answer

sudoers is world writable error

I changed the /ect file permissions on Ubuntu 12.10 so that i could edit bash.bashrc so that neo4j can see the JVM but now I am getting errors when i try run the neo4j server I entered the code below and I managed to edit bash.bashrc but now i cant…
Mike Barnes
  • 4,217
  • 18
  • 40
  • 64
14
votes
2 answers

neo4j and max open files

I'm using neo4j 1.8M06 on ubuntu. When I start it, I get this warning: WARNING: Max 1024 open files allowed, minimum of 40 000 recommended. what does it mean? If it is required, how can I adjust this setting? I've seen this thread on the issue but…
Yaron Naveh
  • 23,560
  • 32
  • 103
  • 158
13
votes
4 answers

How to store tree data in a Lucene/Solr/Elasticsearch index or a NoSQL db?

Say instead of documents I have small trees that I need to store in a Lucene index. How do I go about doing that? An example node in the tree: class Node { String data; String type; List children; } In the above node the "data"…
Golam Kawsar
  • 760
  • 1
  • 8
  • 21
13
votes
3 answers

What can an RDBMS do that Neo4j (and graph databases) cant?

“A Graph Database –transforms a–> RDBMS” The Neo4j site seems to imply that whatever you can do in RDBMS, you can do in Neo4j. Before choosing Neo4j as a replacement for an RDBMS, I need some doubts answered. I am interested in Neo4j…
Jesvin Jose
  • 22,498
  • 32
  • 109
  • 202
13
votes
2 answers

Neo4j Server vs. Embedded

I'am a little bit confused about what is the best solution for my application. As I've seen so far, I have to choose between neo4j standalone (RestGraphDatabase) and an EmbeddedGraphDatabase (the RemoteGraphDatabase is not for production use yet).…
Alebon
  • 1,189
  • 2
  • 11
  • 24
13
votes
1 answer

Where can I find apoc.conf for Neo4j Desktop?

Need to set apoc.import.file.enabled=true in apoc.conf, but cannot find it anywhere.
user11879807
  • 251
  • 1
  • 3
  • 11
13
votes
1 answer

Rails 3 and graph databases

A Rails 3 application running on Postgresql needs to switch to a graph database to be able to grow up. There are many of them and they all offer different kind of API, REST mostly. I am highly inspired by talks of Emil Eifrem, CEO of…
mcmlxxxiii
  • 913
  • 1
  • 9
  • 21
13
votes
4 answers

Storing binary objects in Neo4j

Neo4j doesn't seem to allow me to store binary objects. Does this mean I must used Neo4j in conjuntion with another data store, such as the filesystem., Oracle, etc?
yazz.com
  • 57,320
  • 66
  • 234
  • 385
1 2 3
…
99 100