Which of the following generally has better performance when accessing larger databases?

NAS (Network Attached Storage) uses file-level access over standard Ethernet, introducing additional protocol overhead that limits throughput and IOPS compared to block-level SAN storage.

A SAN provides block-level storage access over a dedicated, high-speed network (typically Fibre Channel or iSCSI), which allows database servers to interact with storage as if it were locally attached. This low-latency, high-throughput architecture is specifically optimized for I/O-intensive workloads like large databases, where the overhead of file-level protocols significantly degrades performance.

CIFS (Common Internet File System) is a file-sharing protocol that runs on top of NAS infrastructure, not a storage architecture itself, and adds latency unsuitable for large database performance.

NFS (Network File System) is a file-level protocol similar to CIFS and, while usable for some database workloads, introduces protocol overhead that reduces performance compared to block-level SAN storage.