Redis基本数据类型和相关操作
Redis资料汇总 http://blog.nosqlfan.com/html/3537.html Redis命令参考 http://www.redisdoc.com/en/latest/ 在线尝试Redis网站 http://try.redis.io/ Redis: Re mote Di ctionary S erver Redis支持的健数据类型 字符串类型 string 散列表类型 hash 列表类
Redis资料汇总 http://blog.nosqlfan.com/html/3537.html
Redis命令参考 http://www.redisdoc.com/en/latest/
在线尝试Redis网站 http://try.redis.io/
Redis: Remote Dictionary Server
Redis支持的健值数据类型
字符串类型 string
散列表类型 hash
列表类型 list
集合类型 set
有序集合类型 zset
Redis安装
redis-server Redis服务器
redis-cli Redis命令行客户端
redis-benchmark 性能测试工具
redis-check-aof AOF文件修复工具
redis-check-dump RDB文件检查工具
Redis命令
KEYS pattern 获得符合规则的键名列表
EXISTS key 判断一个键是否存在
DEL key 删除一个键
TYPE key 获得键值的数据类型
字符串数据类型 STRING
字符串类型是Redis基本数据类型，能存储任何形式的字符串，包括二进制数据。
SET key value 赋值
GET key 取值
INCR key 递增数字(所有Redis命令都是原子操作)
Redis键命名实践 “对象类型:对象ID:对象属性”，对于多个单词推荐用.分割。如键user:1:friends表示ID为1的用户的好友列表。
INCRBY key increment 增加指定整数
DECRBY key decrement 减少指定的整数
INCRBYFLOAT key increment 增加指定浮点数
APPEND key value 向尾部追加值，返回追加后字符串的长度
STRLEN key 返回键值的长度
MGET key [key ...] 获取多个健值
MSET key value [key value ...] 设置多个键值
位操作
GETBIT key offset 获得一个字符串指定位置的二进制位的值(0或1)
SETBIT key offset value 设置字符串类型键指定位置的二进制值，返回该位置的旧值
BITCOUNT key [start] [end] 统计字符串类型中值为1的二进制位个数，可以指定字节的范围
BITOP operation destkey key [key...] (AND, OR, XOR, NOT)
散列类型 HASH
散列类型的键值也是一种字典结构，其存储了字段和字段值的映射，但字段值只能是字符串，不支持其他类型。（集合类型也不支持数据类型嵌套）
HSET key field value 赋值（插入时返回1，更新时返回0）
HGET key field 取值
HMSET key field value [field value ...]
HMGET key field [feild...]
HGETALL key
HEXISTS key field 判断字段是否存在
HSETNX key field value 当字段不存在时赋值
HINCRBY key field increment 增加数字
HDEL key field [field...] 删除字段
HKEYS key 只获取字段名
HVALS key 只获取字段值
HLEN key 获得字段数量
列表类型 LIST
列表类型可以存储一个有序的字符串列表，常用的操作是向列表两端添加元素或者获得某个列表的某一个片段。
内部使用双向链表实现，获取越接近两端的元素速度就越快，不过索引访问元素比较慢。列表类型能非常快速地完成关系数据库难以应付的场景，如社交网络新鲜事。
LPUSH key value [value...] 从列表左边增加元素
RPUSH key value [value...] 从列表右边增加元素
LPOP key 从列表左边弹出元素
RPOP key 从列表右边弹出元素
LLEN key 获取列表中元素的个数
LRANGE key start stop 获取列表片段（包括stop，支持负数表示从最右边开始计数）
LREM key count value 删除前count个值为value的元素（count>0时从左边开始删除，count
LINDEX key index 获取指定索引的元素值
LSET key index value 设置指定索引的元素值
LTRIM key start end 只保留指定片段
LINSERT key FEFORE|AFTER pivot value 首先从左到右查找pivot元素，再根据第二个参赛将value插入该元素前面或后面。
RPOPLPUSH source destination 将一个元素转移到另一个列表 ，原子操作。当source和destination相同时会不断将对尾元素移到队首，实现网站监控系统。
集合类型 SET
集合类型每个元素不同，且无序。
SADD key member [member...] 增加元素，返回成功加入元素的个数
SREM key member [member...] 删除元素
SMEMBERS key 获得集合中所有元素
SISMEMBER key member 判断是否存在集合中
集合间运算
SDIFF [destination] key [key ...] 多个集合求差运算A-B，并存储到destination中
SINTER [destination] key [key ...] 多个集合执行交运算
SUNION [destination] key [key...] 多个集合求并运算
SCARD key 集合中元素个数
SRANDMEMEBER key [count] 随机获得集合中元素(当count>0时随机获取count个不重复元素，count
SPOP key 从集合中随机弹出一个元素
有序集合类型 ZSET
列表类型通过链表实现，获取靠近两端的数据速度极快，当元素增加后中间元素比较慢，更适合"新鲜事"或“日志”这样很少访问中间元素的应用。
有序集合类型通过散列表和跳跃表实现的，所以即使读取位于中间位置也很快O(NlgN)。
列表中不能简单调整某个元素位置，有序集合可以。有序集合更耗费内存。
ZADD key score member [score member...] 加入一个元素和该元素的分数（分数可以是整数或小数，+inf和-inf表示正负无穷）
ZSCORE key member 获得元素的分数
ZRANGE key start stop [WITHSCORE] 按照从从小到大的顺序返回start和stop之间所有元素（WITHSCORE表示带上分数）复杂度O(logn+m)
ZREVRANGE key start stop [WITHSCORE] 从大到小的顺序
ZRANGEBYSCORE key min max [WITHSCORE] [LIMIT offset count] 按照从小到大返回分数在min和max之间的元素
ZINCRBY key increment member 增加某个元素的分数
ZCARD key 获得集合中元素个数
ZCOUNT key min max 获得指定范围内的元素个数
ZREM key member [member ...] 删除一个或多个元素
ZREMRANGEBYRANK key start stop 按照元素分数从小到大的顺序删除指定排名范围内的所有元素，并返回删除元素的个数
ZREMRANGEBYSCORE key min max 删除指定分数范围内的所有元素
ZRANK key member 获得元素的排名
ZREVRANK key member
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