Hi Mattias, Thanks for the replies. Now I have a much more clarity about neo4j.
On Fri, Feb 19, 2010 at 6:41 PM, Mattias Persson <matt...@neotechnology.com>wrote: > Hi Sunil, > > 2010/2/19 Sunil Khedar <su...@truesparrow.com>: > > Hi All, > > > > I was going through the neo4j API. There are few things in API that are > not > > clear to me: > > > > 1. What other configuration options can be set for neo4j, apart from > > storeDir? As in API all configuration related parameter methods are > either > > depricated or will be soon. > A new configuration API will hopefully make it into version 1.1. Until > then, please look at > http://wiki.neo4j.org/content/Configuration_Settings > > > > 2. Can I traverse nodes using "INCOMING" or "OUTGOING" directions, if > they > > have BOTH direction relations? > Relationships are always directed, so they always have a start node > and an end node. This means that a relationship only have a direction > given a context, i.e. what is the direction of relationship (A) if > you're looking at it from node (N). Direction can be ignored in > traversals and when you get relationships for a node, and this is > where the BOTH direction is used. > > > > 3. How DynamicRelationshipType is different from RelationshipType? > Following > > is mentioned in API: > > "Dynamic relationship type is persisted only when the first relationship > of > > this type is created." > > I think DynamicRelationshipType is of no use untill it's used for the > > first time. Please correct me if I am wrong. > DynamicRelationshipType is just a simple implementation of > RelationshipType interface in that it only implements the name() > method. RelationshipType is just a wrapper around a String really and > it specifies the name of the relationship type. Either you use enums > to list your relationship type, so that they become compile-time > checked in your code, f.ex: > > public enum MyRelationshipTypes implements RelationshipType > { > KNOWS, > LOVES, > } > > ...or you can do it on the fly at runtime via f.ex. > DynamicRelationshipType.withName( "KNOWS" ). The result of using the > one or the other is identical. > > > > 4. How EmbeddedReadOnlyGraphDatabase and EmbeddedGraphDatabase are > > different? As both of them are able to create nodes? Are nodes created by > > EmbeddedReadOnlyGraphDatabase non-persistent? I think I am missing > something > > here. > You cannot modify the graph in an EmbeddedReadOnlyGraphDatabase. The > methods are there, but you'll get a RuntimeException when calling > f.ex. createNode(). > > > > 5. How to make sure that ASYNC_OTHER_TX related indexing jobs are not > lost? > > How these jobs are triggered? > Currently they aren't persisted, so if your indexing is critical, > stick with the default configuration. > > > > 6. Can we define custom ReturnableEvaluator and StopEvaluator? > Sure, just create implementations of those classes and pass such > instances into the Node.traverse method. > > > > 7. While creating a node can we define the node id? If no, I think we > have > > to use lucene in-order to get the node ids. Please correct me if there is > > any other way. > No, the node (and relationship) ids are internal and you could rely on > an IndexService (see http://components.neo4j.org/neo4j-index/) for > lookups about other properties, f.ex. "uri" or "username" or such. > > > > > > Thanks, > > Sunil > > > > -- > > Sr. Software Architect > > Center of Excellence (COE) > > True Sparrow Systems > > _______________________________________________ > > Neo mailing list > > User@lists.neo4j.org > > https://lists.neo4j.org/mailman/listinfo/user > > > > > > -- > Mattias Persson, [matt...@neotechnology.com] > Neo Technology, www.neotechnology.com > _______________________________________________ > Neo mailing list > User@lists.neo4j.org > https://lists.neo4j.org/mailman/listinfo/user > -- Thanks, Sunil Sr. Software Architect Center of Excellence (COE) True Sparrow Systems _______________________________________________ Neo mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user
