In Azure, how can an organization ensure data integrity during active operations of multiple replicas of a SQL database?

To ensure data integrity during active operations of multiple replicas of a SQL database, employing synchronous replication is the most effective approach. Synchronous replication guarantees that any changes made to the primary database are immediately and reliably copied to all replicas before the transaction is considered complete. This means that data is consistent across all replicas at any given point in time, which is essential for applications that require high data integrity and real-time consistency.

In contrast, other strategies such as sharding, caching, or eventual consistency do not provide the same level of immediate data integrity across replicas. Sharding involves partitioning the database to distribute workload, but it does not directly address consistency across replicas. Data caching improves performance by storing frequently accessed data closer to the application but does not ensure that the replicated data remains synchronized with the primary source. Eventual consistency allows for temporary inconsistencies between replicas, prioritizing availability and performance over instant synchronization, which can lead to data integrity issues during concurrent operations. Hence, synchronous replication stands out as the ideal method for maintaining data integrity in this scenario.