redis_hyperloglog.hpp

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#pragma once
#include "../acl_cpp_define.hpp"
#include <vector>
#include "../stdlib/string.hpp"
#include "redis_command.hpp"

#if !defined(ACL_CLIENT_ONLY) && !defined(ACL_REDIS_DISABLE)

namespace acl
{

class ACL_CPP_API redis_hyperloglog : virtual public redis_command
{
public:
        /**
         * see redis_command::redis_command()
         */
        redis_hyperloglog(void);

        /**
         * see redis_command::redis_command(redis_client*)
         */
        redis_hyperloglog(redis_client* conn);

        /**
         * see redis_command::redis_command(redis_client_cluster*)
         */
        redis_hyperloglog(redis_client_cluster* cluster);

        ACL_CPP_DEPRECATED
        redis_hyperloglog(redis_client_cluster* cluster, size_t max_conns);

        redis_hyperloglog(redis_client_pipeline* pipeline);

        virtual ~redis_hyperloglog(void);

        /**
         * 将任意数量的元素添加到指定的 HyperLogLog 里面
         * add the specified elements to the specified HyperLogLog
         * @param key {const char*} 指定 key 值
         *  the key
         * @param first_element {const char*} 元素集合的第一个元素值，非空字符串
         *  the first element of the elements list, and the last must be NULL
         *  in the elements list
         * @return {int} 操作是否成功，同时表明是否发生了变更，返回值含义如下：
         *  return the follow values:
         *  1：操作成功，且数据发生了变更（新增数据或老数据发生变更）
         *     successful, and the data was varied
         *  0：修改老数据未发生变化
         *     nothing was changed after modifying the old data
         * -1：出错或对应的 key 对象非 hyperloglog 对象
         *     error or the keh isn't a hyperloglog type
         */
        int pfadd(const char* key, const char* first_element, ...);
        int pfadd(const char* key, const std::vector<const char*>& elements);
        int pfadd(const char* key, const std::vector<string>& elements);

        /**
         * 获得给定键列表的 HyperLoglog 去重后元素的近似数量
         * return the approximated cardinality of the set(s) observed by
         * the hyperloglog at key(s)
         * @param first_key {const char*} key 集合的第一个 key，非空字符串
         *  the firs key which must not be NULL of the keys list, and the
         *  last parameter must be NULL in keys' list
         * @return {int} 键列表集合中经去重后元素的近似数量
         */
        int pfcount(const char* first_key, ...);
        int pfcount(const std::vector<const char*>& keys);
        int pfcount(const std::vector<string>& keys);

        /**
         * 将多个 HyperLogLog 合并（merge）为一个 HyperLogLog ， 合并后的
         * HyperLogLog 的基数接近于所有输入 HyperLogLog 的可见集合的并集
         * merge multiple different hyperloglogs into a single one
         * @param dst {const char*} 目标存储 HyperLogLog 对象的键值
         *  the single key as the destination
         * @param first_src {const char*} 源对象集合中第一个源 HyperLogLog 对象的键
         *  the first source key which must not be NULL in the sources list,
         *  and the last one must be NULL showing the end of the list
         * @return {bool} 操作是否成功，返回 false 表明出错或目标/源对象非
         *  HyperLogLog 对象
         *  true on success, false if the error or the dest/src are not
         *  hyperloglog
         */
        bool pfmerge(const char* dst, const char* first_src, ...);
        bool pfmerge(const char* dst, const std::vector<const char*>& keys);
        bool pfmerge(const char* dst, const std::vector<string>& keys);
};

} // namespace acl

#endif // !defined(ACL_CLIENT_ONLY) && !defined(ACL_REDIS_DISABLE)