`KEYS`

Return every key matching the glob pattern (cross-shard gather).

语法	`KEYS pattern`
分组	scan
参数个数	2
起始版本	1.0.0
标志	readonly
复杂度	O(N) keys in the whole keyspace — every shard walks its entire map, plus an O(P*K) glob match per key
Redis 兼容性	full