How does Voldemort compare to Cassandra? I'm not talking about size of community and only want to hear from people who have actually used both. Especially I'm interested in: How they dynamically scale when adding and removing nodes Query performance How they scale when adding nodes (linear)? Write speed ...
Can I configure Cassandra dynamically without having to edit XML to create columns? ...
I am learning about the Apache Cassandra database [sic]. Does anyone have any good/bad experiences with deploying Cassandra to less than dedicated hardware like the offerings of Linode or Slicehost? I think Cassandra would be a great way to scale a web service easily to meet read/write/request load... just add another Linode running...
Surely one can run a single node cluster but I'd like some level of fault-tolerance. At present I can afford to lease two servers (8GB RAM, private VLAN @1GigE) but not 3. My understanding is that 3 nodes is the minimum needed for a Cassandra cluster because there's no possible majority between 2 nodes, and a majority is required for r...
I'm trying to learn how to map the entities/actors/objects/things in my application for storage in Cassandra. There was a great tutorial for Redis on modeling Twitter data and typical access patterns called Retwis [1]. I've found a couple of examples for Cassandra. How did you start to gain an intuition for Cassandra's data model? [...
Hello all, For a bit of background - this question deals with a project running on a single small EC2 instance, and is about to migrate to a medium one. The main components are Django, MySQL and a large number of custom analysis tools written in python and java, which do the heavy lifting. The same machine is running Apache as well. Th...
Question about Cassandra Why the hell on earth would anybody write a database ENGINE in Java ? I can understand why you would want to have a Java interface, but the engine... I was under the impression that there's nothing faster than C/C++, and that a database engine shouldn't be any slower than max speed, and certainly not use garba...
When experimenting with Cassandra I've observed that Cassandra listens to the following ports: TCP *:8080 TCP *:8888 TCP *:57311 TCP *:57312 TCP 127.0.0.1:7000 TCP 127.0.0.1:9160 UDP 127.0.0.1:700 How does Cassandra use each of the ports listed? ...
When experimenting with Cassandra I've observed that Cassandra writes to the following files: /.../cassandra/commitlog/CommitLog-<id>.log /.../cassandra/data/Keyspace1/Standard1-1-Data.db /.../cassandra/data/Keyspace1/Standard1-1-Filter.db /.../cassandra/data/Keyspace1/Standard1-1-Index.db /.../cassandra/data/system/LocationInfo-1-Data....
Is there any robust way of implementing Cassandra back end to a web application developed using Django web framework. Thanks ...
Hi, I got an out put on my Windows command line when I execute the following .bat file bin\cassandra.bat and here's the out put that I'm getting on my command line Drive already SUBSTed Starting Cassandra Server Listening for transport dt_socket at address: 8888 INFO - Sampling index for E:\myfirstapp\cassandra\data\system\LocationI...
I'm working on a project that is considering using Cassandra as a database. We would like to eventually migrate to Cassandra even if we use MySQL to start with, given its scalability. I know that big companies like Facebook, Digg, and recently Twitter is using Cassandra, but I don't believe any of those sites run off Rails. My questio...
I have managed to set up Cassandra + Thrift and the Python wrapper for Thrift LazyBoy, and I have followed an example mentioned in the LazyBoy Wiki.After testing that example I'm getting an error with an exception. cassandra.ttypes.InvalidRequestException: InvalidRequestException(why='Keyspace UserData does not exist in this schema.') ...
Hey guys, Im working on promising project that develops a new social media app for web and mobile. We are at begin defining functionalities. Nevertheless, I'm thinking ahead on architecture. So I'm asking: 1 - Whats the best plataform to develop the core of this aplication that will have a Rest API interface. 2 - Whats the best databa...
In Cassandra, I have the following Column Family: <ColumnFamily CompareWith="TimeUUIDType" Name="Posts"/> I'm trying to insert a record into it as follows using a C++ generated function generated by Thrift: ColumnPath new_col; new_col.__isset.column = true; /* this is required! */ new_col.column_family.assign("Posts"); new_col.super_...
Assume two Cassandra nodes running on hosts A and B respectively. Which TCP and/or UDP ports needs to be open between hosts A and B for Cassandra to operate properly? ...
I'm doing some work with Cassandra and the Thrift libraries. I realize these are very early libraries and will (undoubtedly) change at some point. I've been using the following link for help with setting up my C# code to write and read to and from my Cassandra server (which I have running in an Ubuntu Server instance in my local Virtua...
Consider a 500 million row MySQL table with the following table structure ... CREATE TABLE foo_objects ( id int NOT NULL AUTO_INCREMENT, foo_string varchar(32), metadata_string varchar(128), lookup_id int, PRIMARY KEY (id), UNIQUE KEY (foo_string), KEY (lookup_id), ); ... which is being queried using only the following t...
I'm working with very long time series -- hundreds of millions of data points in one series -- and am considering Cassandra as a data store. In this question, one of the Cassandra committers (the über helpful jbellis) says that Cassandra rows can be very large, and that column slicing operations are faster than row slices, hence my quest...
Sorry if this question is somewhat subjective. I am new to 'could store', 'distributed store' or some concepts like this. I really wonder what do they have in common and want to get an overview on all of them. What do I need to prepare if I want to write a product similar to this? ...