I am new to OrientDB, using OrientDB 2.2.20. How do I move a vertex in an existing cluster using Gremlin
Following move vertex command is in SQL
MOVE VERTEX (select * from SClosure where (eType="DSLAM")) TO CLUSTER:myCluster
The inner query gets the #rid to be moved to an existing cluster "myCluster"
Is there a Gremlin version of this query? It is needed for my requirement
Related
I have deployed a test trino cluster composed by a coordinator and one node.
I have defined several catalogs, all PostgreSQL database, I am am trying to execute some simple operation as
describe analysis_n7pt_sarar4.public.tests_summary;
or
show tables from analysis_n7pt_sarar4.public like '%sub_step%'
From trino webpage I found the queries blocke at 9% and everything seems hanging.
If I execute queries such as:
select * from analysis_n7pt_sarar4.public.bench limit 5
or
select count(*) from analysis_n7pt_sarar4.public.tests_summary;
I obtain results in some seconds.
In http-request.log I found no errors in both coordinator and worker.
What shoudl I check?
Thanks
I am new to orientdb. I use orientdb verson 2.1.11.
I config and deployed five nodes on the same machine in distribute mode. I use console to create a database, command is (port 2425 is the second node):
create database remote:192.168.12.37:2425/fuwu_test root 1234 plocal graph
Every node created the database "fuwu_test", but the cluster not create synchronous relationship.
I see the studio that every cluster has one cluster not five. I create one class Person, the class also not syncronized to other nodes.
Why it does't work, how to create a new datebase in running a cluster. Do I need to restart the whole nodes ?
thanks a lot
There is a known issue on this in v2.1 and v2.2 releases. The workaround is creating the database before to go in cluster. Anyway it will be resolved soon, sorry.
This morning I decided to try out Titan. I've used both Neo4j and OrientDB, and was going to implement a polyglot persistence model using one of those graph databases; however, since I am already using Cassandra, I decided to try out Titan.
I've read through the Titan docs, as well as the Tinkerpop docs, but a few things are still unclear. Both Neo4j and OrientDB are pretty much plug-and-play; since Titan seems like more of a layer on top of a db backend like Cassandra, I'm unsure of how to start with setting it up. I can start the gremlin console and connect to my Cassandra cluster, and I can start titan server, both from the console.
My main question is, am I supposed to install titan as a service? Do I make my own init scripts, or use supervisor/monit/etc to manage it? Basically, what is the right way to keep everything running and available?
Titan starts as an application by itself; configuring and running embedded applications of backends (Berkeley, Embedded-Cassandra, ...) or connects to already started server or cluster of Cassandra or DynamoDB.
This means that you can pass a single configuration file that includes all information you want Titan to use. In this config file, you could ask Titan to embed a backend (start and maintain it by itself) or connect to a local/remote instance.
These are several examples of config files that you should have a look at.
As a quick introduction, download Titan 1.0.0 and run its gremlin console by moving to main directory and running
bin/gremlin.sh
Inside the gremlin console, you could run something like
TitanGraph g = TitanFactory.build().
set("storage.backend", "berkeleyje").
set("storage.directory", "/tmp/graph").
open();
Or you could load a configuration file like this:
TitanGraph g = TitanFactory.open("path/to/properties/file")
Dive deep here.
I have a one node hadoop cluster set up. I am trying to execute SPARK Scripts from my edge node to hit the hadoop node through SSH. I am looking for how to execute SPARK scripts from edge node to hit the hadoop node(where my spark exists). Any command? Any settings?
You need to use spark-submit.
Scaling multiple schemas on multiple machine, I am using PostgreSQL as backend system, now I want to perform the lookup of schema that on which machine the schema resides, so like I have two machines M1 and M2 on both of the machines D1 and D2 are installed now tenant1 schema is on DB1 and Tenant2 schema is on DB2, now both the tenants will use the same application server, either in this case I have to use cluster and partition nodes and every node contain some amount of data or the like. The same application can be used by tenant1 and tenant2, now I want some solution to stay in the middle and perform lookup and caching of the pooling. Is it possible to get it done by using Cluster ? Or I have to make a program like PgPool II that appears as Database Sever and lookup the schema for me.
I would suggest one of two things.
You could use pgpool or application-level connection pooling to make the decision.
If you need it to be db-transparent you could set up schemas with pl/proxy procedures to handle sharding of the db out in this way. This would allow you to have your "front-end" database servers coordinate queries for the storage shards (each in a different partition).