What are "Cassandra triggers" used for?

Cassandra triggers are specifically designed to execute custom Java code in response to data operations such as inserts, updates, or deletes. This feature allows developers to implement custom logic that runs automatically whenever specific conditions are met during these operations. For instance, a trigger can be used to modify data before it is stored, perform validations, or even send notifications upon certain actions.

When a data operation is performed on a table that has a trigger associated with it, the trigger activates and runs the defined functionality. This capability enhances the flexibility of data management in Cassandra, allowing for tailored processing based on the application's requirements.

Other options do not accurately describe the purpose of triggers. While tasks like backing up data, enforcing schema changes, or optimizing storage space are important in a database context, they fall outside the specific functionalities provided by triggers. Instead, triggers focus entirely on executing user-defined Java code, making them a powerful tool for customizing data operations in Cassandra.