Cassandra - Introduction

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Cassandra - Introduction

What is Cassandra

Apache Cassandra is a NoSQL Database. It is highly scalable, high-performance and distributed database designed to handle large amounts of data across many commodity servers, providing high availability with no single point of failure.

In the definition we used many terms like NoSQL, Commodity Server etc. Let us understand these terminology one by one to understand the Cassandra definition

NoSQL Database

A NoSQL database is a database that provides a mechanism to store and retrieve data in non-relational format (as oppose to RDBMS Database)
These databases are schema free, can handle huge amount of data and support easy replication to support fault tolerance. NoSQL Database does not support transactions and it is eventually consistent (while RDBS database follows ACID (Atomicity, Consistency, Isolation, and Durability)).
Beside Cassandra there are many NoSQL database platforms available in the market such as

1.Apache Spark
2.Apache Storm
3.Google BigQuery
4.Ceph
5.DataTorrent RTS
6.Disco
7.Pachyderm
8.Presto
9.Hydra
10.Misco
11.Qizmt
12.MongoDB
etc...etc....

Commodity Hardware?

Commodity Hardware is really inexpensive affordable and easy to obtain Computers.

Features of Cassandra

Cassandra offers verity of features which makes it one of the popular NoSQL database among others. Below are the highlights of Features offered by Cassandra

Fast writes - Cassandra performs fast writes and can store hundreds of terabytes of data without compromising the read efficiency.

Easy data distribution - Cassandra provides the flexibility to distribute data where you need by replicating data across multiple data centers.

Elastic scalability - Cassandra is highly scalable. it allows to add more hardware to accommodate more customers and more data as per requirement.

Always on architecture - Cassandra provides high availability. It has no single point of failure and it is continuously available for business-critical applications.

Fast linear-scale performance - Cassandra is linearly scalable, i.e., it increases your throughput as you increase the number of nodes in the cluster.

Flexible data storage - Cassandra accommodates all possible data formats including: structured, semi-structured, and unstructured. It can dynamically accommodate changes to your data structures according to your need.

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