Cassandra Overview

Cassandra - A Overview

Cassandra: - Cassandra was developed in 2008 by AvinashLakshman and Prashant Malik. The developer of Cassandra is Apache Software Foundation. It is written in Java. It is an open source distributed database management system designed to handle large amounts of data across many commodity servers, providing high availability with no single point of failure. Cassandra achieves the highest throughput for the maximum number of nodes in all experiments" although "this comes at the price of high write and read latencies.

Features

v  Decentralized

Every node in the cluster has the same role. There is no single point of failure.

v  Supports replication and multi data center replication

Replication strategies are configurable. Cassandra is designed as a distributed system, for deployment of large numbers of nodes across multiple data centers.

v  Scalability

Read and write throughput both increase linearly as new machines are added, with no downtime or interruption to applications.

v  Fault-tolerant

Data is automatically replicated to multiple nodes for fault-tolerance. Replication across multiple data centers is supported. Failed nodes can be replaced with no downtime.

v  Tunable consistency

Writes and reads offer a tunable level of consistency, all the way from "writes never fail" to "block for all replicas to be readable", with the quorum level in the middle.

v  MapReduce support

Cassandra has Hadoop integration, with MapReduce support. There is support also for Apache Pig and Apache Hive.

v  Query language

Cassandra introduces CQL (Cassandra Query Language), a SQL-like alternative to the traditional RPC interface. Language drivers are available or Java (JDBC), Python(DBAPI2), Node.JS (Helenus) and Go (gocql).

Advantages

Ø  It offers robust support for clusters spanning multiple datacenters.

Ø  Its performance is high.

Disadvantage

Cassandra does not support joins or subqueries.