Can someone help us to know how to explore janusgraph database functions ?
DRAY <ani...@...>
Can someone help us to know how to explore janusgraph database functions used in Gremlin language and also best approach to start using and understanding janusgraph ( to create own graph data having vertexs and edges with the commands to understand better and to explore further ) We wanted to use graph database and its features in our Company and has been assigned a project to explore graph database and specially janusgraph - we are going through the janusgraph website but couldn't get detail info on janusgraph functions and its usage and also to create own graph data. So our request is to please help us on the same to explore janusgraph. Thank you in Advance, Appreciate your support.
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Best (Correct?) Way to Access JanusGraph Remotely
zbec...@...
Hello, I am in the process of building a Java, RPC server that takes in multi-threaded requests, queries the database and returns a result to the client. I understand JanusGraph allows concurrent transactions and I would prefer all requests run within their own transaction. However, I am a bit confused as to access JanusGraph remotely as I have seen multiple implementations. The first uses:
Then I would call the following in each request block of the RPC server:
But this appears to building a JanusGraph server. Is that correct? Another implementation I have seen is:
Then simply close the client at the end of each request. However this GraphTraversalSource does not support transactions, I believe the second option is more correct, but do Client instances maintain transactions? Are they transactions themselves? Any kind of explanation or clarity would be greatly appreciated.
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Getting RowTooBigException while firing janus query backed by hbase
Priyanka Jindal <priyanka...@...>
Hi In my case janusgraph storage is backed by hbase and i am firing the following query: query = tx.query().has("key1","v1").has("key2","v2").limit(FIXED_VALUE) for(T element : query.properties()){ } It contains the composite index. vertex is not partitioned. So now while calling query.properties() it fails with "org.apache.hadoop.hbase.regionserver.RowTooBigException: org.apache.hadoop.hbase.regionserver.RowTooBigException: Max row size allowed: 1073741824, but the row is bigger than that." exception from hbase side. As per my understanding, the reason for this is : the row which is getting fetched from hbase is greater than the threshold value set by hbase. And a row corresponds to the edges and properties of single vertex. So my question is: 1. When the above query is invoked, how exactly it works? Does it try to fetch all the vertices and then filter depending on passed key value pairs? 2. I have tried increasing value of threshold value of hbase, but even then getting the same error. What could be the reason for that
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Re: Adding this property for key [~T$SchemaName] and value [...] violates a uniqueness constraint
BO XUAN LI <libo...@...>
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Re: Adding this property for key [~T$SchemaName] and value [...] violates a uniqueness constraint
Matteo Lissandrini <matteo.l...@...>
So there is no way to have a graph with a property name and an edge label with the same name?
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On Monday, 10 August 2020 at 18:28:48 UTC+2 li...@... wrote: Yeah, that's possible. You need to make sure properties and labels don't have the same name.
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Re: Adding this property for key [~T$SchemaName] and value [...] violates a uniqueness constraint
Boxuan Li <libo...@...>
Yeah, that's possible. You need to make sure properties and labels don't have the same name.
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On Tuesday, August 11, 2020 at 12:25:46 AM UTC+8 Matteo Lissandrini wrote:
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Re: Adding this property for key [~T$SchemaName] and value [...] violates a uniqueness constraint
Matteo Lissandrini <matteo.l...@...>
I am loading a graph from scratch in an empty database. Could it be that there may be an edge label and a property name with the same name?
On Monday, 10 August 2020 at 18:21:36 UTC+2 li...@... wrote:
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Re: Adding this property for key [~T$SchemaName] and value [...] violates a uniqueness constraint
BO XUAN LI <libo...@...>
Are you running the code against a clean database? Does the property already exist before you run this piece of code?
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Re: Adding this property for key [~T$SchemaName] and value [...] violates a uniqueness constraint
Matteo Lissandrini <matteo.l...@...>
Hi Boxuan, thanks for the reply. This is the full error: org.janusgraph.core.SchemaViolationException: Adding this property
for key [~T$SchemaName] and value [rtns8_designation] violates a
uniqueness constraint [SystemIndex#~T$SchemaName] I actually run a distinct before creating the schema here is the relevant piece of code https://pastebin.com/BaYc5ej5 So I am quite sure I am not creating it twice. Any ideas? Thanks, Matteo
On Sunday, 9 August 2020 at 04:57:43 UTC+2 li...@... wrote: Hi Matteo,
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Re: Index on subquery not working
Veerle <vvanbe...@...>
Thanks for the answer but putting has(“property”, true) before both(“connected”) changes the results of the query. I actually simplefied my query a bit for my question here but what I want is a query that selects all relations where on one side the property is true and on the other side the property is false. Something like this: V() .hasLabel("road") .has("property", true) .both("connected") .hasLabel("road") .has("property", false) .next() The first part of the query uses the index, but the second part isn't. Thanks, Veerle
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Re: Index on subquery not working
BO XUAN LI <libo...@...>
Hi Veerle,
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Try putting both(“connected”) after has(“property”, true). Regards, Boxuan
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Index on subquery not working
Veerle <vvanbe...@...>
Hi, I do have a graph with about 1 million vertexes and a many to many relation between those vertexes. The vertexes are I created a mixed index management.buildIndex(indexName, Vertex.class) .addKey(management.getPropertyKey("property")) .indexOnly(road) .buildMixedIndex("search"); The index is working correctly, I can see it popping up in the profile output: graph But when I want to have the same on the other side of the "connected" relation, the index is not used anymore. graph .profile().next() Does someone know how I get the subquery to use the index? Thanks a lot, Veerle
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Re: HA about janusGraph
Vayne Yang <vayne...@...>
Hi Marc, I see, Thank you so much!
On Monday, August 10, 2020 at 5:21:38 PM UTC+8, HadoopMarc wrote:
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Re: HA about janusGraph
HadoopMarc <bi...@...>
Hi Vayne Yang, Query failing to a DOWN node because of a wrong node selection seems unlikely because JanusGraph uses the regular cassandra/cql drivers. The similar thread below suggests to look into the gremlin-server logs for QUORUM warnings and to also configure the replication-factor on the janusgraph side. HTH, Marc Op maandag 10 augustus 2020 om 10:44:00 UTC+2 schreef Vayne Yang:
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Re: HA about janusGraph
Vayne Yang <vayne...@...>
Hi Marc, Best wishes!
On Monday, August 10, 2020 at 2:43:00 PM UTC+8, HadoopMarc wrote:
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Re: HA about janusGraph
Vayne Yang <vayne...@...>
Hi Marc, Is that means, JanusGraph itself is HA right? If so, maybe the problem is that read-consistency-level=QUORUM is too strict. Sorry I can't repeat the error immediately. if I run into this problem again, I will report here. Thanks for your help !
On Monday, August 10, 2020 at 2:43:00 PM UTC+8, HadoopMarc wrote:
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add SINGLE type edge for two partitioned vertex can not duplicate removal
Moon Hu <199512...@...>
- Janusgraph Version: 0.0.3 - Storage Backend: hbase 1.2.6 - Mixed Index Backend:elasticsearch 6.3.0 I have two partitioned vertex ,vertex id is 57402 and 30245090, and i defined a SIMPLE type edge named 'father', i add this relation for the vterices ten times, i can query ten relations from graph
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Re: HA about janusGraph
HadoopMarc <bi...@...>
Hi Vayne Yang, Can you eleborate on "the query may be failed"? Is it just a warning followed by an automatic new attempt or does the query produce no result? Can you add the stacktrace? Best wishes, Marc Op maandag 10 augustus 2020 om 08:13:41 UTC+2 schreef Vayne Yang:
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Re: HA about janusGraph
Vayne Yang <vayne...@...>
hi Marc! Thanks for your reply! I am pretty sure the spaces are not the problems. e.g. https://docs.janusgraph.org/basics/example-config/#cassandra-remote configured in the same way. And after open the configure file with JanusGraphFactory, gremlin console also print 'standardjanusgraph[cql:[172.1.1.1, 172.1.1.2, 172.1.1.3, 172.1.1.4]]'.
On Monday, August 10, 2020 at 1:34:01 PM UTC+8, HadoopMarc wrote:
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Re: Can't add a vertex with long property value - ERROR Connection reset by peer
Kenn Falcon <kennf...@...>
Thx
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在2020年8月6日星期四 UTC+8 下午9:56:51<HadoopMarc> 写道:
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