Cassandra Concepts: Difference between revisions

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=Overview=
=Overview=


Cassandra is a key-value database.
Cassandra is NoSQL a key-value database. It provides continuous availability with no single point of failure. The database uses a ring design and consistent hashing. In a ring design there is no master node, all nodes are identical and communicate with each other as peers. This architecture allows it to scale horizontally, by incrementally adding nodes with no reconfiguration. Provides good performance for large amounts of data.


=CQL=
=CQL=

Revision as of 20:49, 25 September 2019

Internal

Overview

Cassandra is NoSQL a key-value database. It provides continuous availability with no single point of failure. The database uses a ring design and consistent hashing. In a ring design there is no master node, all nodes are identical and communicate with each other as peers. This architecture allows it to scale horizontally, by incrementally adding nodes with no reconfiguration. Provides good performance for large amounts of data.

CQL

Cassandra Query Language

SELECT "email" FROM "user_tweets" WHERE "username" = 'john';

Schema

Keyspace

Keyspace Operations

Table

Row

Column

Partition Key

Has primary key, or lookup key semantics.