My question would be, Is it possible to change from Cassandra to PostGreSQL in Thingsboard PE because I'm more comfortable with PostgreSQl, and I need only the JSON data to be queried.
It would be great to get some suggestions.
Related
I have downloaded Gremlin Server with an intention of being able to use Gremlin to traverse a Neo4j DB.
Now, speaking of the latter, it has to be somehow added to the Gremlin Server installation, but I have difficulty finding any up-to-date guidance on how to do that. There are a few posts here on SO describing various kinds of problems people run into, but no definitive solution, much less one for the current versions of both Tinkerpop and Neo4j.
Would appreciate specific links, tips etc.
Thanks!
There is a "TIP" describing Gremlin Server configuration in the TinkerPop reference documentation found here. Basically, you -install Neo4j dependencies:
bin/gremlin-server.sh install org.apache.tinkerpop neo4j-gremlin 3.3.4
then you edit your Gremlin Server YAML configuration file to connect to your database. Gremlin Server contains a sample file to get you started and is found the /conf directory of the installation. Of critical note is this entry:
graphs: {
graph: conf/neo4j-empty.properties}
It specifies the Neo4j configuration to use and the sample one that ships with Gremlin Server looks like this:
gremlin.graph=org.apache.tinkerpop.gremlin.neo4j.structure.Neo4jGraph
gremlin.neo4j.directory=/tmp/neo4j
gremlin.neo4j.conf.dbms.auto_index.nodes.enabled=true
gremlin.neo4j.conf.dbms.auto_index.relationships.enabled=true
As you can see, the configuration basically just passes through Neo4j specific configuration to Neo4j itself. Only the first two lines are TinkerPop options. In this case, it sets up Neo4j for embedded mode, meaning Neo4j runs within the Gremlin Server JVM. You can make Gremlin Server part of a Neo4j HA cluster with instructions found in the reference documentation here.
Note that you asked for "current" versions of both TinkerPop and Neo4j. While these instructions are current for TinkerPop, I'm afraid that the Neo4j version TinkerPop supports is well behind their latest release. It would be nice if someone had time to issue a pull request for that.
How to connect or load data from Kafka to neo4j. I saw Mazerunner, DocManager in Neo4j documentation to connect Neo4j with Spark and MongoDB. Is there any such kind of projects related to Kafka and neo4j.
Thanks.
Please check this GitHub project. This is with Neo4j 2.2.3 KernelExtention.
Link: https://github.com/ducky427/neo-kafka
You may need to change the settings code for any 3.0.x version.
Another way, if you are using Neo4j Embedded version, you can simply integrate these through your custom API.
Do share, if you have found other ways to integrate.
Following on from the information found in the blog post titled 'Neo4j 2.1.2 – Maintenance Release', I thought I should check the consistency of a database that has been upgraded to Neo4j 2.1.1.
My set up: Neo4j community edition running on Windows Server 2012 R2 - the binary distribution running as a Windows service (NOT the windows desktop launcher executable).
In the blog post it talks about using the backup tool included with the enterprise version of Neo4j so I have downloaded an evaluation copy (2.1.4) so have access to Neo4jBackup.bat. I cannot however, get a backup to run. No matter what I try I get
Couldn't connect to '127.0.0.1:6362'
or a variation thereof.
I am running
.\bin\Neo4jBackup.bat -from localhost -to D:\DataBackups\Neo4j\check
I have tried specifying a port, specifying IP address, using single://localhost. After consulting the manual more closely I have also amended my config to add
# Enable online backups to be taken from this database.
online_backup_enabled=true
# Port to listen to for incoming backup requests.
online_backup_server=127.0.0.1:6362
Still I receive the same error. I am clearly being a moron. What am I doing wrong? Help!
The question boils down to 'how do I back up a community edition database as alluded to in this Neo4j blog post?
OK so yes. I am a moron. It just came to me. You need to open the database with the enterprise edition!
For anyone who is overcome with a moment of stupidity, like me
Copy the database you wish to check (graph.db by default) to the data directory of your evaluation copy of Neo4j
Start up Neo4j (you may or may not need a store upgrade)
Run .\bin\Neo4jBackup.bat -from localhost -to [your desired backup location]
Sit back and await the results
Feel free to mock/throw rotten vegetables etc at me....! :)
Starting with the 2.1 line (somewhere around 2.1.5 I think) the consistency checker was moved from the enterprise edition to the community edition. It is therefore now possible to check a DB with the community edition too. In the root of the neo4j server directory run:
java -cp 'lib/*' org.neo4j.consistency.ConsistencyCheckTool data/graph.db
Note that this is not an offical API (it's undocumented).
I'm working on a project that is considering using Ruby on Rails and Cassandra as a database.
I have referred some website https://github.com/cequel/cequel/ to connect rails with Cassandra but some problem in finding cequel:configuration generator.
How do i migrate Cassandra data with ruby on rails?
Thank you
Please update what is the error you are getting while using cequel.
There are also various other options you can use,
datastax-rails (If you are using Datastax)
cql-rb
Cassandra Migrations
Cassandra Object
There is also a stackoverflow post for Rails ORM with Cassandra
http://en.wikipedia.org/wiki/MariaDB
MariaDB is a community-developed branch of the MySQL database, the
impetus being the community maintenance of its free status under the
GNU GPL, as opposed to any uncertainty of MySQL license status under
its current ownership by Oracle. The contributors are required to
share their copyright with Monty Program AB.
The page goes on to say that MariaDB 5.5 is binary-compatible with the MySQL of the same version and adds a couple of database engines of its own to choose from.
I also read that Fedora 19 is going to remove MySQL packages in favor of MariaDB.
So the question is, is Ruby on Rails 3+ MariaDB compatible? Are there any future plans to integrate MariaDB features as they start to deviate from MySQL?
Red Hat, Debian, Fedora, OpenSuse, Slackware, and even Wikipedia moved (or are moving) to MariaDB. This means it is stable. Also, MariaDB (and Percona Server) seems to fix security issues much faster than Oracle.
Since MariaDB is compatible with MySQL, all APIs are compatible, including Ruby on Rails API.
(Well, MariaDB 10.0 is not totally compatible with MySQL 5.6, but the incompatibilities are not at API-level!)
You can use Mariadb with any compatible MySQL client. I am using MySQL .NET connector and it just work.