MongoDB Overview

Distributed Document Database (分布式文档数据库)

• NoSQL
• Rich JSON (BSON)
• schema-less (弱模式)
• Scale-Out (横向扩展)

Scenario (应用场景)

• 小文件(Rich JSON和二进制文件)存储 (相比于HDFS)
• 弱事务性业务数据
• 物联网
• 日志
• 爬虫数据

Fundamental Concepts (基础概念)

Schema

• database (数据库)
• collection (集合)
  • index (索引)
    • Unique Indexes
    • TTL Indexes
  • Capped Collections: fixed size, FIFO
• document (文档): BSON
• field (字段)

Deployment (部署)

• standalone (单节点)
• replica set (副本集)
• sharded cluster (分片集群)

Storage Engines (存储引擎)

• WiredTiger
• In-Memory
• pluggable storage engine API (自定义)

Document Field Types (文档字段类型)

• ObjectId: _id
• int (32-bit)
• long (64-bit)
• string
• date (UTC datetime in milliseconds, 64-bit signed integer)
• boolean
• null
• double
• decimal
• BinData
• object
• array
• Regular Expression
• timestamp (for internal MongoDB use, use date instead)
• undefined
• symbol

References

• MongoDB Documentation