To maintain good read performance in a constantly changing database, which two components are utilized?

To maintain good read performance in a constantly changing database, utilizing delta storage is crucial. Delta storage is designed to handle changes, such as inserts, updates, and deletes, efficiently without significantly impacting the performance of read operations. This component allows for the separation of current transactional data from historical or less frequently accessed data, optimizing read access patterns by keeping the most frequently accessed information readily available.

Delta storage also ensures that the system can manage data modifications while still providing quick access to the data for analytical processing, by accumulating changes before they are merged into the main storage. This process minimizes locking and contention for read access, enhancing the overall performance of the system.

While other components like the column store play a role in how data is organized and accessed, it's the delta storage specifically that addresses the need for maintaining optimal reading capabilities amidst continuous data changes. The column store provides efficient storage for analytical queries, and memory and main storage focus more on the holistic aspect of data storage rather than the specifics of read performance amidst changes.