What is the concept of Cassandra database?

Cassandra is a highly scalable, distributed database management system originally developed by Facebook, and later became a top-level project of the Apache Foundation. It is designed to handle large amounts of data, providing high availability and scalability.

Cassandra’s data model is based on key-value pairs, where each pair corresponds to a row that consists of multiple columns. Rows are sorted based on keys and can have multiple column families, each containing multiple columns. The distribution of data in Cassandra is achieved through consistent hashing algorithm, where data is distributed across multiple nodes and can be replicated for reliability and fault tolerance.

Cassandra provides a flexible data model and powerful query language that allows you to query and manipulate data using CQL (Cassandra Query Language). It also supports transactions to ensure data consistency.

In general, Cassandra is a distributed database management system that is suitable for large-scale data sets and high concurrent access, with advantages in availability, scalability, and performance.