RNeo4j cypher - retrieving paths - r

I'm trying to extract a sub-graph from a global network (sub-networks of specific nodes to a specific depth).
The network is composed of nodes labeled as Account with a property of iban and relationships of TRANSFER_TO_AGG.
The cypher syntax is as followed:
MATCH (a:Account { iban :'FR7618206004274157697300156' }),(b:Account),
p = allShortestPaths((a)-[:TRANSFER_TO_AGG*..3]-(b))
RETURN p limit 250
This works perfectly on the Neo4J web interface. However, when trying to save the results to an R object using the command cypher I get the following error:
"Error in as.data.frame.list(value, row.names = rlabs) :
supplied 92 row names for 1 rows"
I believe this is due to the fact that if returning data, you can only query for tabular results. That is, this method has no current functionality for Cypher results containing array properties, collections, nodes, or relationships.
Can anyone offer a solution ?

I've recently added functionality for returning pathways as R objects. First, uninstall / reinstall RNeo4j. Then, see:
?getSinglePath
?getPaths
?shortestPath
?allShortestPaths
?nodes
?rels
?startNode
?endNode
For your query specifically, you would use getPaths():
library(RNeo4j)
graph = startGraph("http://localhost:7474/db/data/")
query = "
MATCH (a:Account { iban :'FR7618206004274157697300156' }),(b:Account),
p = allShortestPaths((a)-[:TRANSFER_TO_AGG*..3]-(b))
RETURN p limit 250
"
p = getPaths(graph, query)
p is a list of path objects. See the docs for examples of using the apply family of functions with a list of path objects.

Related

NebulaGraph Database: when I filter edges by their property values, it shows incorrect results

Here are some details:
NebulaGraph version is 3.2.1
Deployment way is distributed
Installation way is RPM
Disk is Non-SSD
CPU and memory information are Single node 4core8g
Specific description of the problem
I use the following nGQL to query the 2-hop path data with vid of 76517618765348
MATCH p=(v)-[e:`belong`*2]-(v2)
WHERE id(v) IN ["76517618765348"]
AND ALL(l IN e WHERE l.create_long == 1665368234) RETURN p LIMIT 100
The results are as shown in the figure below
Among them, the edge belong has the property of which type is long and name create_long. When I use the == to query the edge with a value of 1665368234 to filter. Why can’t I find the corresponding data?
The real data relationship is as shown in the figure below
Are you sure you would like to filter all edges with this WHERE clause: WHERE l.create_long == 1665368234?
MATCH p=(v)-[e:`belong`*2]-(v2)
WHERE id(v) IN ["76517618765348"]
AND ALL(l IN e WHERE l.create_long == 1665368234) RETURN p LIMIT 100
As you are using == here, I guess maybe you actually would like to express one of the edge in list of e fulfills create_long == 1665368234?
If it’s the case as I guessed, you should instead use ANY instead of ALL here:
And that is:
MATCH p=(v)-[e:`belong`*2]-(v2)
WHERE id(v) IN ["76517618765348"]
AND ANY(e_ IN e WHERE e_.create_long == 1665368234)
RETURN p LIMIT 100

Neo4J and Cypher query

I am new to Neo4j and Cypher query.My create query is like each Shop has 2 chillers which has 2 PLCs each which in turn has 2 sensors each.
The create is as below
Create(:SHOP{name:"Shop1"})-[:hasChiller]->(:CHILLER{name:"Chiller1"})
Create(:SHOP{name:"Shop1"})-[:hasChiller]->(:CHILLER{name:"Chiller2"})
Create(:SHOP{name:"Shop2"})-[:hasChiller]->(:CHILLER{name:"Chiller3"})
Create(:SHOP{name:"Shop2"})-[:hasChiller]->(:CHILLER{name:"Chiller4"})
Create(:CHILLER{name:"Chiller1"})-[:hasPLC]->(:PLC{name:"Plc1"})
Create(:CHILLER{name:"Chiller1"})-[:hasPLC]->(:PLC{name:"Plc2"})
Create(:CHILLER{name:"Chiller2"})-[:hasPLC]->(:PLC{name:"Plc3"})
Create(:CHILLER{name:"Chiller2"})-[:hasPLC]->(:PLC{name:"Plc4"})
Create(:CHILLER{name:"Chiller3"})-[:hasPLC]->(:PLC{name:"Plc5"})
Create(:CHILLER{name:"Chiller3"})-[:hasPLC]->(:PLC{name:"Plc6"})
Create(:CHILLER{name:"Chiller4"})-[:hasPLC]->(:PLC{name:"Plc7"})
Create(:CHILLER{name:"Chiller4"})-[:hasPLC]->(:PLC{name:"Plc8"})
Create(:PLC{name:"Plc1"})-[:hasSensor]->(:SENSOR{name:"Sensor1"})
Create(:PLC{name:"Plc1"})-[:hasSensor]->(:SENSOR{name:"Sensor2"})
Create(:PLC{name:"Plc2"})-[:hasSensor]->(:SENSOR{name:"Sensor3"})
Create(:PLC{name:"Plc2"})-[:hasSensor]->(:SENSOR{name:"Sensor4"})
Create(:PLC{name:"Plc3"})-[:hasSensor]->(:SENSOR{name:"Sensor5"})
Create(:PLC{name:"Plc3"})-[:hasSensor]->(:SENSOR{name:"Sensor6"})
Create(:PLC{name:"Plc4"})-[:hasSensor]->(:SENSOR{name:"Sensor7"})
Create(:PLC{name:"Plc4"})-[:hasSensor]->(:SENSOR{name:"Sensor8"})
Create(:PLC{name:"Plc5"})-[:hasSensor]->(:SENSOR{name:"Sensor9"})
Create(:PLC{name:"Plc5"})-[:hasSensor]->(:SENSOR{name:"Sensor10"})
Create(:PLC{name:"Plc6"})-[:hasSensor]->(:SENSOR{name:"Sensor11"})
Create(:PLC{name:"Plc6"})-[:hasSensor]->(:SENSOR{name:"Sensor12"})
Create(:PLC{name:"Plc7"})-[:hasSensor]->(:SENSOR{name:"Sensor13"})
Create(:PLC{name:"Plc7"})-[:hasSensor]->(:SENSOR{name:"Sensor14"})
Create(:PLC{name:"Plc8"})-[:hasSensor]->(:SENSOR{name:"Sensor15"})
Create(:PLC{name:"Plc8"})-[:hasSensor]->(:SENSOR{name:"Sensor16"})
However the Match to get the sensors under SHOP1
MATCH(s:SHOP{name:"Shop1"})-[:hasChiller]->(cc:CHILLER)-[:hasPLC]->(pp:PLC)-[:hasSensor]->(ss:SENSOR) return ss.name
returns nothing.Says no changes and no data.
I am trying this out on Neo4J sandbox environment.I did this based on the understanding i had using match clause in SQL SERVER GRAPH 2019 where this works.
Can anyone point out where i am going wrong?
You are improperly creating multiple instances of the "same" node. You should create each node once, and then use its bound variable name later on when you need to create relationships involving that node.
Delete all your data and follow this pattern instead (you have to fill in the "..." parts):
CREATE
(sh1:SHOP{name:"Shop1"}), (sh2:SHOP{name:"Shop1"}),
(c1:CHILLER{name:"Chiller1"}), (c2:CHILLER{name:"Chiller2"}),(c3:CHILLER{name:"Chiller3"}), (c4:CHILLER{name:"Chiller4"}),
(p1:PLC{name:"Plc1"}), ..., (p8:PLC{name:"Plc8"}),
(se1:SENSOR{name:"Sensor1"}), ..., (se16:SENSOR{name:"Sensor16"}),
(sh1)-[:hasChiller]->(c1), (sh1)-[:hasChiller]->(c2),
... // create remaining relationships using bound variable names for nodes

Assign query using 'match()' to subgraph

I have a JanusGraph database with a graph structure as follows:
(Paper)<-[AuthorOf]-(Author)
I'm want to use Gremlin's match clause to query the data and assign the results to a subgraph. This is what I have so far:
g.V().match(
__.as('a').has('Paper','paperTitle', 'The name of my paper'),
__.as('a').in('AuthorOf').outV().as('b')).
select('b').values()
This query returns what I want, the Authors of the paper I'm for which I'm searching. However, I want to assign the results to a subgraph so I can export it using:
sg.io(IoCore.graphml()).writeGraph("/home/ubuntu/myresults.graphml")
Previously, I've achieved this with a different query structure like this:
sg = g.V().has('paperTitle', 'The name of my paper').
inE('AuthorOf').subgraph('sg1').
outV().
cap('sg1').
next()
Is there away to achieve the same results using the 'match()' statement?
After a little trial and error I was able to create a working solution:
sg = g.V().match(
__.as('a').has('Paper','paperTitle', 'ladle pouring guide'),
__.as('a').inE('AuthorOf').subgraph('sg').outV().as('b')).
cap('sg').next()
At first, I was trying to use the 'select' statement to isolate the subgraph. After reviewing the documentation on 'subgraph' and learning more about side-effects in gremlin I realized it wasn't necessary.

Printing/Fetching Vertex values from a path

Just getting started with gremlin.
Printing out all the Vertex values worked out fine
gremlin> g.V().values()
==>testing 2
==>Cash Processing
==>Sales
==>Marketing
==>Accounting
I was able to find all the directly connected path between my Vertices.
gremlin> g.V().hasLabel('Process')
.repeat(both().simplePath())
.until(hasLabel('Process'))
.dedup().path()
==>[v[25],v[28]]
==>[v[25],v[26]]
==>[v[26],v[27]]
==>[v[26],v[25]]
Now am trying to print out the values in the path like ['Sales', 'Accounting'] instead of [v[25],v[28]]
Not been able to figure out a way yet
Already tried and failed with
Unfold: Does not get me 1-1 mapping
gremlin> g.V().hasLabel('Process').repeat(both().simplePath()).until(hasLabel('Process')).dedup().path().unfold().values()
==>Cash Processing
==>Accounting
==>Cash Processing
==>Sales
==>Sales
==>Marketing
==>Sales
==>Cash Processing
Path seems to be of a different data-type and does not support .values() function
gremlin> g.V().hasLabel('Process')
.repeat(both().simplePath())
.until(hasLabel('Process'))
.dedup().path().values()
org.apache.tinkerpop.gremlin.process.traversal.step.util.ImmutablePath cannot be cast to org.apache.tinkerpop.gremlin.structure.Element
Tried the following google searches and didnt get the answer
gremlin print a path
gremlin get values in a path
and few more word twisting
Found one at here that was for java but that didnt work for me
l = []; g.V().....path().fill(l)
(but cant create list, Cannot set readonly property: list for class: org.apache.tinkerpop.gremlin.structure.VertexProperty$Cardinality
)
I have running it on Gremlin console (running ./gremlin.sh)
You can use the by step to modulate the elements inside the path. For example by supplying valueMap(true) to by you get the properties of the vertices, together with the vertex labels and their ids:
gremlin> g.V().repeat(both().simplePath()).times(1).dedup().path().by(valueMap(true))
==>[[id:1,name:[marko],label:person,age:[29]],[id:3,name:[lop],lang:[java],label:software]]
==>[[id:1,name:[marko],label:person,age:[29]],[id:2,name:[vadas],label:person,age:[27]]]
==>[[id:1,name:[marko],label:person,age:[29]],[id:4,name:[josh],label:person,age:[32]]]
==>[[id:2,name:[vadas],label:person,age:[27]],[id:1,name:[marko],label:person,age:[29]]]
==>[[id:3,name:[lop],lang:[java],label:software],[id:6,name:[peter],label:person,age:[35]]]
==>[[id:4,name:[josh],label:person,age:[32]],[id:5,name:[ripple],lang:[java],label:software]]
I used the modern graph which is one of TinkerPop's toy graphs that are often used for such examples. Your output will look a bit different and you may want to use something else than valueMap(true) for the by modulator. The TinkerPop documentation of the path step itself contains two more advanced examples for path().by() that you might want to check out.

Creating graph in titan from data in csv - example wiki.Vote gives error

I am new to Titan - I loaded titan and successfully ran GraphOfTheGods example including queries given. Next I went on to try bulk loading csv file to create graph and followed steps in Powers of ten - Part 1 http://thinkaurelius.com/2014/05/29/powers-of-ten-part-i/
I am getting an error in loading wiki-Vote.txt
gremlin> g = TitanFactory.open("/tmp/1m") Backend shorthand unknown: /tmp/1m
I tried:
g = TitanFactory.open('conf/titan-berkeleydb-es.properties’)
but get an error in the next step in load-1m.groovy
==>titangraph[berkeleyje:/titan-0.5.4-hadoop2/conf/../db/berkeley] No signature of method: groovy.lang.MissingMethodException.makeKey() is applicable for argument types: () values: [] Possible solutions: every(), any()
Any hints what to do next? I am using groovy for the first time. what kind of groovy expertise needed for working with gremlin
That blog post is meant for Titan 0.4.x. The API shifted when Titan went to 0.5.x. The same principles discussed in the posts generally apply to data loading but the syntax is different in places. The intention is to update those posts in some form when Titan 1.0 comes out with full support of TinkerPop3. Until then, you will need to convert those code examples to the revised API.
For example, an easy way to create a berkeleydb database is with:
g = TitanFactory.build()
.set("storage.backend", "berkeleyje")
.set("storage.directory", "/tmp/1m")
.open();
Please see the docs here. Then most of the schema creation code (which is the biggest change) is now described here and here.
After much experimenting today, I finally figured it out. A lot of changes were needed:
Use makePropertyKey() instead of makeKey(), and makeEdgeLabel() instead of makeLabel()
Use cardinality(Cardinality.SINGLE) instead of unique()
Building the index is quite a bit more complicated. Use the management system instead of the graph both to make the keys and labels, as well as build the index (see https://groups.google.com/forum/#!topic/aureliusgraphs/lGA3Ye4RI5E)
For posterity, here's the modified script that should work (as of 0.5.4):
g = TitanFactory.build().set("storage.backend", "berkeleyje").set("storage.directory", "/tmp/1m").open()
m = g.getManagementSystem()
k = m.makePropertyKey('userId').dataType(String.class).cardinality(Cardinality.SINGLE).make()
m.buildIndex('byId', Vertex.class).addKey(k).buildCompositeIndex()
m.makeEdgeLabel('votesFor').make()
m.commit()
getOrCreate = { id ->
def p = g.V('userId', id)
if (p.hasNext()) {
p.next()
} else {
g.addVertex([userId:id])
}
}
new File('wiki-Vote.txt').eachLine {
if (!it.startsWith("#")){
(fromVertex, toVertex) = it.split('\t').collect(getOrCreate)
fromVertex.addEdge('votesFor', toVertex)
}
}
g.commit()

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