华夏棋牌

目录 搜索
Cluster cluster addslots(集群 槽位) cluster count failure reports(集群计数掉落败申报) cluster countkeysinslot cluster delslots cluster failover cluster forget cluster getkeysinslot cluster info cluster keyslot(集群键槽) cluster meet cluster nodes(集群节点) cluster replicate(集群复制) cluster reset(集群重置) cluster saveconfig cluster set config epoch cluster setslot cluster slaves cluster slots readonly readwrite Connection auth echo ping quit select swapdb Geo geoadd geodist geohash geopos georadius georadiusbymember Hashes hdel hexists hget hgetall hincrby hincrbyfloat hkeys hlen hmget hmset hscan hset hsetnx hstrlen hvals HyperLogLog pfadd pfcount pfmerge Keys del dump exists expire expireat keys migrate move object persist pexpire pexpireat pttl randomkey rename renamenx restore scan sort touch ttl type unlink wait Lists blpop brpop brpoplpush lindex linsert llen lpop lpush lpushx lrange lrem lset ltrim rpop rpoplpush rpush rpushx Pub/Sub psubscribe publish pubsub punsubscribe subscribe unsubscribe Scripting eval evalsha script debug script exists script flush script kill script load Server bgrewriteaof bgsave client getname client kill client list client pause client reply client setname command command count command getkeys command info config get config resetstat config rewrite config set dbsize debug object debug segfault flushall flushdb info lastsave monitor role save shutdown slaveof slowlog time Sets sadd scard sdiff sdiffstore sinter sinterstore sismember smembers smove spop srandmember srem sscan sunion sunionstore Sorted Sets zadd zcard zcount zincrby zinterstore zlexcount zrange zrangebylex zrangebyscore zrank zrem zremrangebylex zremrangebyrank zremrangebyscore zrevrange zrevrangebylex zrevrangebyscore zrevrank zscan zscore zunionstore Strings append bitcount bitfield bitop bitpos decr decrby get getbit getrange getset incr incrby incrbyfloat mget mset msetnx psetex set setbit setex setnx setrange strlen Transactions discard exec multi unwatch watch
文字

EXISTS key [key ...]

自1.0.0起可用。

时间严重年夜度: O(1)

前往假定key存在。

自 Redis 3.0.3 以来,可以指定多个密钥而不是单个密钥。在这类情形下,它会前往现有密钥的总数。请重视,为单个键前往1或0只是可变参数应用的特例,是以该敕令完全向后兼容。

用户应当知道,假定一再再三在参数中提及类似的现有密钥,它将被一再再三计数。以是假定somekey存在,EXISTS somekey somekey将前往2。

前往值

整数回复,详细为:

  • 1 假定密钥存在。

  • 0 假定密钥不存在。

自 Redis 3.0.3 以来,该敕令吸收可变数目的键并将前往值阻拦了归纳综合:

  • 存在于指定为参数的键中的键的数目。键提及一再再三,现有计数一再再三。

例子

redis>  SET key1 "Hello" "OK" 

redis>  EXISTS key1 (integer) 1 

redis>  EXISTS nosuchkey (integer) 0 

redis>  SET key2 "World" "OK" 

redis>  EXISTS key1 key2 nosuchkey (integer) 2

上一篇: 下一篇: