Andreas Ronge writing about using Neo4j in embedded mode with JRuby:
The advantage of the embedded Neo4j is better performance due to the direct use of the Java API. This means you can write queries in plain Ruby! Another advantage of the embedded Neo4j is that since it’s an embedded database there is one less piece of infrastructure (the database server) to install. The embedded database is running in the same process as your (Rails) application. Since JRuby has real threads there is no need to start up several instances of the database or of the Ruby runtime since JRuby can utilize all available cores on the CPU. There is actually even no need to start the database at all as it will be started automatically when needed. Notice it’s still possible to use the REST protocol or the web admin interface from an embedded Neo4j, see the neo4j-admin gem.
So which should I choose ? Well, if you can’t use JRuby or you don’t need an Active Model compliant Neo4j binding then the Neo4j Server is a good choice, otherwise I would suggest using the embedded Neo4j.rb gem (but I’m a bit biased)
As showed also by the earlier [migrating data from Oracle to MongoDB with JRuby], JRuby proves to be an interesting beast for handling data. I’m more on the side of Python, but Jython is not (yet?) as up-to-date as JRuby.
Original title and link: An Overview of Neo4j.rb 2.0 ( ©myNoSQL)