PREFIX.DIGESTOrder-insensitive checksum of a prefix's rows for migration verification.
| 语法 | PREFIX.DIGEST prefix |
| 分组 | migration |
| 参数个数 | 2 |
| 起始版本 | 3.0.0 |
| 标志 | readonly, extension |
| 复杂度 | O(keys on the shard) to walk plus O(sum of row sizes) to digest, on every shard. Per-row digests XOR together, so the result is order-insensitive and safe across shard counts |
| Redis 兼容性 | kevy-only: nearest is DEBUG DIGEST — comparable in kind (Redis also XORs per-key digests), but Redis's is whole-DB and lives behind DEBUG, while ours is per-prefix (the unit a migration actually cares about) and is a supported verb |