Hi, how do you guys expect indexing for relationships to work? Would it be an index just as for nodes... or per node? I often hear that it'd speed up traversals if a node has many, many neighbours. But if the relationship index would be for the entire graph (not per node) that wouldn't really help, would it?
2010/6/21 Craig Taverner <cr...@amanzi.com>: > A side comment, since I think indexing relationships with lucene might be > good, but think there might be alternatives for your current example. > > You said that the relationship property is a float from 0 to 1, so you > cannot use relationship types, but actually, when you consider that any > index is usually created by breaking data ranges (continuous or discrete) > into fewer, more discrete ranges, you can use a relationship type to > represent a range of floats. For example, if you have roughly even > distribution of floats between 0 and 1, try divide that into 100 parts > (0%-100%, or 0.01 to 1.00), and make a relationship type for each. This > would certainly facilitate traversing relationships of specific float values > (at least improve the performance dramatically, as in an index). > > Of course, this example focuses on traversing from a particular document. If > you are searching for all relationships in the entire database with > particular float values, then a separate index would be better. > > On Mon, Jun 21, 2010 at 2:11 PM, Marius Kubatz <marius.kub...@udo.edu>wrote: > >> Hello guys, hello community! >> >> I'm currently evaluating neo4j for my thesis and have a wish :) >> I have already opened a ticket for this,( >> https://trac.neo4j.org/ticket/241 ) but >> I would like to hear what you guys think about it. >> >> Basically it just involves the ability to index Neo4j Relationships with >> Lucene Index. >> >> Neo4j works great on sparse graphs, but what happens when you have a very >> tight graph with several thousands of neighbors to one node? >> Additionally as soon as you store informations on Relationships you will >> get >> into trouble, because you will have to iterate through all those edges to >> find the >> properties you seek. >> >> If this sounds far fetched please take a look at this example where one >> might need properties on Relationships: >> One "Document" node is related to another Document node by a similarity >> function which is stored in the Relationships between those document nodes. >> Lets just say that we save a float between [0 - 1] on those relationships, >> which makes it impossible to create RelationshipTypes for every value. >> >> Using Index to fetch Relationships by their indexed properties would >> greatly >> speed up the process and increase the attractiveness of using properties on >> Relationships. I would love to have quick access to Relationship properties >> where I could add and implement fuzzy >> logic, probabilities, Bayesian networks, similarities, ranking ... and so >> on >> ... As said thank you for Relationship properties, they are great and >> already there, but what I miss is quick access to them. >> >> Thank you very much and best regards! >> >> Marius >> >> -- >> "Programs must be written for people to read, and only incidentally for >> machines to execute." >> >> - Abelson & Sussman, SICP, preface to the first edition >> _______________________________________________ >> Neo4j mailing list >> User@lists.neo4j.org >> https://lists.neo4j.org/mailman/listinfo/user >> > _______________________________________________ > Neo4j mailing list > User@lists.neo4j.org > https://lists.neo4j.org/mailman/listinfo/user > -- Mattias Persson, [matt...@neotechnology.com] Hacker, Neo Technology www.neotechnology.com _______________________________________________ Neo4j mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user
