# streamDB

**Repository Path**: zhaoyao219/streamDB

## Basic Information

- **Project Name**: streamDB
- **Description**: stream db , readonly, subject-based
- **Primary Language**: C++
- **License**: MIT
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 3
- **Created**: 2020-10-14
- **Last Updated**: 2020-12-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# streamDB

#### 介绍
stream db , readonly, subject-based

#### 软件架构
软件架构说明


#### 安装教程

1.  xxxx
2.  xxxx
3.  xxxx

#### 使用说明

1.  xxxx
2.  xxxx
3.  xxxx

#### 参与贡献

1.  Fork 本仓库
2.  新建 Feat_xxx 分支
3.  提交代码
4.  新建 Pull Request

#### dev log

  ---------------------------> cur
  Block  Block  Block  Block  Block

FileStream --> File

FileStream <-- Cache
exist ? : 
    offset =Mapping=> pageNo && 
    pageNo -> offset

Addr:
    Logical Addr -> PageNo -> File + offset
128 * 1024

offset% 128

[0-127] -> 128
[128-255] -> 128


db = DB:Open("file.db");

thread1:
    db->append("message");
    db->append("message");
    db->append("message");
    db->append("message");
    db->append("message");

thread2:
iter = db->read(100);
while(iter.hasNext()){
    iter->next();
}
iter->close();
db->close();


#### Roadmap

###### Unified Cache Layer

1. single Subject

Writer --> Cache  --> Reader
            |
           Subject

2. Multi-Subject

Writers --> Cache(Shard-Locked)  --> Readers
                |
        Sub1, Sub2, Sub3

###### Notify between Consumer & Producer



###### Network