FEED.READRead change-feed frames from one shard past a generation/offset cursor.
| 语法 | FEED.READ shard generation offset [COUNT n] [PREFIX prefix ...] |
| 分组 | feed |
| 参数个数 | -4 |
| 起始版本 | 3.0.0 |
| 标志 | readonly, extension |
| 复杂度 | A single shard (the shard is an argument, not a fan-out). O(log B) to locate the start offset in the backlog plus O(count * frame size) to decode and re-encode. COUNT defaults to 256 and is hard-capped at 4096 |
| Redis 兼容性 | kevy-only: no clean Redis analogue. Keyspace notifications are fire-and-forget with no cursor and no replay; Redis Streams have cursors but are a stream you must dual-write to, not a feed over your existing keyspace; the replication backlog is what this is built on, but Redis exposes it only to replicas. kevy is deliberately not a broker: no consumer groups, no server-side positions, no global cross-shard order |