wedb_embed 0.1.2

Embedded database engine providing Redis-like APIs, built on fjall / 嵌入式数据库引擎，提供类似 Redis 的接口，底层基于 fjall 开发
Documentation 
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/// 默认压缩因子
pub const DEFAULT_COMPRESSION: u32 = 100;
/// 最小压缩因子
pub const MIN_COMPRESSION: u32 = 1;
/// 最大压缩因子
pub const MAX_COMPRESSION: u32 = 1000;
/// 最大缓冲区容量
pub const MAX_CAPACITY: usize = 1024;

/// 计算缓冲区容量 (对标 Apache Kvrocks std::min(compression * 6 + 10, 1024))
#[inline]
pub const fn calculate_capacity(compression: u32) -> usize {
  let cap = compression as usize * 6 + 10;
  if cap > MAX_CAPACITY {
    MAX_CAPACITY
  } else {
    cap
  }
}

/// TDIGEST.CREATE 命令选项
#[derive(Debug, Clone, Copy, PartialEq, Eq, bitcode::Encode, bitcode::Decode)]
pub struct TDigestCreate {
  pub compression: u32,
}

impl Default for TDigestCreate {
  #[inline]
  fn default() -> Self {
    Self {
      compression: DEFAULT_COMPRESSION,
    }
  }
}

/// TDIGEST.MERGE 命令选项
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default, bitcode::Encode, bitcode::Decode)]
pub struct TDigestMerge {
  pub compression: Option<u32>,
  pub override_dest: bool,
}

/// TDIGEST.INFO 命令响应信息（对标 Apache Kvrocks TDigestMetadata & TDIGEST.INFO）
#[derive(Debug, Clone, PartialEq, bitcode::Encode, bitcode::Decode)]
pub struct TDigestInfo {
  pub compression: u32,
  pub capacity: usize,
  pub merged_nodes: usize,
  pub unmerged_nodes: usize,
  pub merged_weight: f64,
  pub unmerged_weight: f64,
  pub total_weight: f64,
  pub observations: u64,
  pub total_compressions: u64,
  pub minimum: Option<f64>,
  pub maximum: Option<f64>,
}