Cassandra Practice Test 2025 – Complete Exam Prep Guide

The statement regarding partition indexes is accurate in that they play a crucial role in locating partitions on disk. In Cassandra, a partition index provides a mapping between the partition keys and their respective locations on disk. This indexing mechanism allows for efficient data retrieval and access, particularly in a distributed system where data is spread across multiple nodes.

When a query is made, the partition index enables the database to quickly identify the specific nodes where the data resides, therefore streamlining retrieval times and minimizing unnecessary disk I/O operations. This makes accessing data more efficient than searching through all data files blindly.

In contrast, the other options do not accurately capture the role of partition indexes in the architecture of Cassandra. They may suggest misconceptions about the functioning and use cases of partition indexes within the database system. Understanding the primary function of partition indexes is essential for anyone looking to optimize data retrieval in Cassandra.