gremlin

问题 I'm going crazy because of this exception when starting up JanusGraph. It happened between restarts of the gremlin-server, without even touching the configuration files. This error always appears at the very first startup of gremlin-server. This is the stack trace from the logs: 6911 [main] INFO org.janusgraph.diskstorage.log.kcvs.KCVSLog - Loaded unidentified ReadMarker start time 2019-08-21T17:57:53.794212900Z into org.janusgraph.diskstorage.log.kcvs.KCVSLog$MessagePuller@51efb731 8148

问题 The Document and the Revision are two objects that reside in our domain logic specific layer. The Document represents an abstraction around any material piece of paper that you could think of. That is - every contract, invoice or drawing could be called a Document . On the other hand, the material representation of the Document is the Revision : the list of paper, that construction engineer receives on site, represents a Revision of the Document that designer has created. If something in a

问题 I would like to be able to specify the neo4j (2.0+) database folder when I open a connection to a graph using bulbs. The goal is to be able to open different or multiple neo4j databases (folders in data/) on the same machine without starting the neo4j server. This works with the Gremlin console. I suspect the route to doing this with bulbs would be to use the bulbs Rexster client (http://bulbflow.com/docs/api/bulbs/rexster/client/) and somehow automatically start a Rexster server pointing to

问题 I am using AWS Neptune with gremlin and I want to get the id of a vertex with all properties of the vertex in one query. How can I do this? I have tried g.V().hasLabel('file').valueMap(true) but the output is: { "fileSize": [ "9170" ], "Gremlin.Net.Process.Traversal.T": "f1fce58306f85ca7050503160640d735c9919c8fc85881d65de80bfe31b5ca24", "mimeType": [ "text/html" ] } No label and no id is there. The problem with project('id','label',' fileSize', 'mimeType', 'malwareSource'). by(id). by(label).

问题 I wanted to model partner relationship like the following, which I expressed in the format of labeled property graph. I wanted to use RDF language to express the above graph, particularly I wanted to understand if I can express the label of the "loves" edge (which is an URI to an article/letter). I am new to RDF, and I know the RDF can easily express the node properties in the LPG, but is it possible to conveniently express the edge properties? A bit more context of this question: the reason

问题 I wanted to model partner relationship like the following, which I expressed in the format of labeled property graph. I wanted to use RDF language to express the above graph, particularly I wanted to understand if I can express the label of the "loves" edge (which is an URI to an article/letter). I am new to RDF, and I know the RDF can easily express the node properties in the LPG, but is it possible to conveniently express the edge properties? A bit more context of this question: the reason

问题 I'm interested in calculating the Jaccard similarity metric for all pairs of vertices in a graph that are not directly connected. The Jaccard metric is defined as the norm of the intersection of the neighbors of the two vertices divided by the norm of the union of the same sets. where So far I have been able to get all pairs of nodes not directly connected (only interested in this case for link prediction, if a direct link already exists then I do not need to calculate the Jaccard metric)

问题 Using Gremlin, I can create a vertex in an Azure Cosmos DB graph by issuing g.addV('the-label').property('id', 'the-id') and subsequently find it using g.V('the-label').has('id', 'the-id') However, I haven't found a way to issue a query that will insert the node if it is missing, and just get the reference to it if it already exists. Is there a way? My concrete use case is that I want to add an edge between two nodes, regardless of whether those nodes (or the edge, for that matter) exist

问题 Is there an easy way to replace or merge vertices and keep/merge existing edges? Or just manually copy all properties from the vertex and recreate existing edges and all (meta-)properties and then drop the superfluous vertex? 回答1: Alright, as mentioned in the comments above, you're going to do the matching in OLTP. That means you'll likely have a concrete entry point. Let's make up a simple sample graph: g = TinkerGraph.open().traversal() // Stackoverflow data g.addV("user").property("login",

问题 I'm trying to understand how this pattern for a conditional insert works: g.V() .hasLabel('person').has('name', 'John') .fold() .coalesce( __.unfold(), g.addV('person').property('name', 'John') ).next(); What is the purpose of the fold/unfold? Why are these necessary, and why does this not work: g.V() .coalesce( __.hasLabel('person').has('name', 'John'), g.addV('person').property('name', 'John') ).next(); The fold-then-unfold pattern seems redundant to me and yet the above does not yield the