Archive for the ‘Neo4jClient’ Category

Lucene Full Text Indexing with Neo4j

Sunday, March 25th, 2012

Lucene Full Text Indexing with Neo4j by Romiko Derbynew.

From the post:

I spent some time working on full text search for Neo4j. The basic goals were as follows.

  • Control the pointers of the index
  • Full Text Search
  • All operations are done via Rest
  • Can create an index when creating a node
  • Can update and index
  • Can check if an index exists
  • When bootstrapping Neo4j in the cloud run Index checks
  • Query Index using full text search lucene query language.

Download:

This is based on Neo4jClient: http://nuget.org/List/Packages/Neo4jClient

Source Code at:http://hg.readify.net/neo4jclient/

Introduction

So with the above objectives, I decided to go with Manual Indexing. The main reason here is that I can put an index pointing to node A based on values in node B.

Imagine the following.

You have Node A with a list:

Surname, FirstName and MiddleName. However Node A also has a relationship to Node B which has other names, perhaps Display Names, Avatar Names and AKA’s.

So with manual indexing, you can have all the above entries for names in Node A and Node B point to Node A only. (emphasis added)

Not quite merging but it is an interesting take on creating a single point of reference.

BTW, search for Neo4j while you are at Romiko’s blog. Several very interesting posts and I am sure more are forthcoming.

Neo4jClient

Sunday, February 26th, 2012

Neo4jClient

From the description:

A .NET client for the neo4j REST API. neo4j is an open sourced, Java based transactional graph database. It’s pretty awesome.

Gremlin vs Cypher Initial Thoughts @Neo4j

Wednesday, February 22nd, 2012

Gremlin vs Cypher Initial Thoughts @Neo4j

Romiko Derbynew writes:

The Neo4jClient now supports Cypher as a query language with Neo4j. However I noticed the following:

  • Simple graph traversals are much more efficient when using Gremlin
  • Queries in Gremlin are 30-50% faster for simple traversals
  • Cypher is ideal for complex traversals where back tracking is required
  • Cypher is our choice of query language for reporting
  • Gremlin is our choice of query language for simple traversals where projections are not required
  • Cypher has intrinsic table projection model, where Gremlins table projection model relies on AS steps which can be cumbersome when backtracking e.g. Back(), As() and _CopySplit, where cypher is just comma separated matches
  • Cypher is much better suited for outer joins than Gremlin, to achieve similar results in gremlin requires parallel querying with CopySplit.
  • Gremlin is ideal when you need to retrieve very simple data structures
  • Table projection in gremlin can be very powerful, however outer joins can be very verbose

So in a nutshell, we like to use Cypher when we need tabular data back from Neo4j and is especially useful in outer joins.

Excellent comparison of Gremlin vs. Cypher. Both have their advantages.