Which two techniques should a large e-commerce company implement to maintain database performance and availability during unplanned events?

• A. Replication and cloud storage
• B. Log shipping and backups
• C. Replication and log shipping
• D. Snapshot testing and mirroring

Answer: (C)

To maintain database performance and availability during unplanned events, implementing replication and log shipping is highly effective.

Replication involves copying and maintaining database objects in multiple databases that make up a distributed database system. By using replication, the e-commerce company can ensure that there are multiple copies of the database available. This redundancy not only enhances data availability but also improves load balancing and disaster recovery capabilities. If one database fails due to an unplanned event, the system can quickly redirect queries to another replicated database, ensuring continuous access for users.

Log shipping is another critical technique where transaction logs from the primary database are automatically backed up and sent to one or more secondary databases. These secondary databases can be kept in a standby mode, ready to take over in case the primary database encounters problems. By regularly shipping these logs, the secondary databases are kept up to date with the most recent transactions, which minimizes data loss and reduces downtime during recovery.

In contrast, while options such as cloud storage provide scalability and flexibility, they do not specifically address immediate database performance and availability during unexpected failures. Similarly, snapshot testing and mirroring can enhance data protection but may not be as effective in providing ongoing transaction processing capabilities during a failure as replication and log shipping do. Thus, combining replication and log