What is the use of "Materialized Views" in Cassandra?

Materialized Views in Cassandra are used to provide alternative query patterns for the underlying data. This feature allows users to create different views of the same data stored in a table, which can optimize for various querying requirements.

In Cassandra, data is structured in such a way (using a wide-column store model) that each table is designed for specific query patterns. However, as application requirements evolve, the need to query the data in different ways can arise. Materialized Views address this by automatically maintaining a separate view of the data, organized in a way that makes these alternative queries efficient and straightforward to execute.

This means that when the data in the base table is updated, the Materialized View is automatically refreshed to reflect those changes, ensuring consistency without requiring additional manual updates or complex queries. As a result, applications can retrieve data more efficiently for different use cases, thereby improving overall performance.

Other options do not accurately capture the primary purpose of Materialized Views or misrepresent their functionality in the context of Cassandra’s architecture.