Questions tagged [cassandra]

Apache Cassandra is a highly scalable, eventually consistent, distributed, structured row store. Questions about Cassandra server administration should be asked on https://dba.stackexchange.com/questions/tagged/cassandra .

Apache Cassandra is a highly scalable, eventually consistent, distributed, structured row/column store. Cassandra brings together the distributed systems technologies from Dynamo and the data model from Google's . Like , Cassandra is eventually consistent. Like BigTable, Cassandra provides a ColumnFamily-based data model richer than typical key/value systems.

Cassandra's Dynamo-based cluster model provides linear scalability and fault tolerance on commodity hardware or cloud infrastructure. Its support for replicating across multiple data centers is best-in-class, providing low latency and the ability to survive entire data center outages.

Cassandra's data model offers the convenience of column indexes with the performance of log-structured updates and powerful built-in caching with the fastest write performance as compared to other database solutions and makes it a compelling option for big data processing. It provides linear scalability with the provision to add/remove nodes on the fly without downtime.

Cassandra was open-sourced by Facebook in 2008 and quickly became a top-level Apache project. Today, it's widely used by companies in many markets.

Official links:

Documentation

Useful Links:

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Cassandra Client Java API's

I have recently started working with Cassandra Database. Now I am in the process of evaluating which Cassandra client we should go forward with. I have seen various post on stackoverflow about which client to use for Cassandra but none has very…
arsenal
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Is there a clear equivalent of 'show keyspaces' in cqlsh 2?

What cqlsh command can I use to quickly see the keyspaces in a cluster? cqlsh does not provide show keyspaces and describe cluster isn't as concise as I want. I'm working using the following specifications: cqlsh 2.2.0, Cassandra 1.1.10, CQL spec…
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MySQL and NoSQL: Help me to choose the right one

There is a big database, 1,000,000,000 rows, called threads (these threads actually exist, I'm not making things harder just because of I enjoy it). Threads has only a few stuff in it, to make things faster: (int id, string hash, int replycount, int…
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Cassandra frozen keyword meaning

What's the meaning of the frozen keyword in Cassandra? I'm trying to read this documentation page: Using a user-defined type, but their explanation for the frozen keyword (which they use in their examples) is not clear enough for me: To support…
Alon
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What are the differences between a node, a cluster and a datacenter in a cassandra nosql database?

I am trying to duplicate data in a cassandra nosql database for a school project using datastax ops center. From what I have read, there is three keywords: cluster, node, and datacenter, and from what I have understand, the data in a node can be…
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Sorted String Table (SSTable) or B+ Tree for a Database Index?

Using two databases to illustrate this example: CouchDB and Cassandra. CouchDB CouchDB uses a B+ Tree for document indexes (using a clever modification to work in their append-only environment) - more specifically as documents are modified…
Riyad Kalla
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Install python@2 on Mac with M1 chip

Long story short, I want to install Apache Cassandra on a MacBook Pro with M1 chipset. In order to install it, one must install other softwares before, one of them being python which must be updated to the latest version. I have followed this…
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Cassandra cqlsh "unable to connect to any servers"

I get the following message when executing cqlsh.bat on the command line Connection error: ('Unable to connect to any servers', {'127.0.0.1': ProtocolError("cql_version '3.3.0' is not supported by remote (w/ native protocol). Supported versions:…
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Results pagination in Cassandra (CQL)

I am wondering how can I achieve pagination using Cassandra. Let us say that I have a blog. The blog lists max 10 posts per page. To access next posts a user must click on pagination menu to access page 2 (posts 11-20), page 3 (posts 21-30),…
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Whats the difference between Paxos and W+R>=N in Cassandra?

Dynamo-like databases (e.g. Cassandra) can enforce consistency by means of quorum, i.e. a number of synchronously written replicas (W) and a number of replicas to read (R) should be chosen in such a way that W+R>N where N is a replication factor. On…
user1128016
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Redis, CouchDB or Cassandra?

What are the strengths and weaknesses of the various NoSQL databases available? In particular, it seems like Redis is weak when it comes to distributing write load over multiple servers. Is that the case? Is it a big problem? How big does a service…
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Comparison : Aerospike vs Cassandra

Both Aerospike and Cassandra says they are better than the other in their own respective benchmarks. Reference : http://java.dzone.com/articles/benchmarking-cassandra-right and a few others. Has anyone used both of them? Is Aerospike as good as…
holmes840
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How does Voldemort compare to Cassandra?

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…
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How to do a join queries with 2 or more tables in cassandra cql

I am new to cassandra. Here I have two tables EVENTS and TOWER. I need to join those for some queries. But I'm not enable to do it. Structure of EVENTS table: eid int PRIMARY KEY, a_end_tow_id text, a_home_circle text, a_home_operator text, a_imei…
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Why HBase is a better choice than Cassandra with Hadoop?

Why is using HBase a better choice than using Cassandra with Hadoop? Can anyone please give a detailed explanation on this? Thanks
Niladri Biswas
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