Data modeling in 30 seconds 

A brief overview of the Apache Cassandra data model.

Apache Cassandra™ is a partitioned row store. It is an open-source, distributed-database system that is designed for storing and managing large amounts of data across commodity servers.

You design the data model 
The design of the data model is based on the queries you want to perform, not on modeling entities and relationships like you do for relational databases.
Keyspace 
The outermost grouping of data, similar to a schema in a relational database. All tables go inside a keyspace. A keyspace is the defining container for replication.
Table 
A table stores data based on a primary key, which consists of a partition key and optional clustering columns.
  • A partition key defines the node on which the data is stored.
  • A clustering column defines the order of data stored in a row.
  • A primary key is used to access the data in the table.
    Note: In earlier versions of Apache Cassandra, a column family was synonymous in many respects, to a table.
Cassandra table
Cassandra table

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