NoSQL探索1：认识MongoDB

- 基本特性，直接引用官网描述

Combining the best features of document databases, key-value stores, and RDBMSes.

MongoDB (from "humongous") is a scalable, high-performance, open source, schema-free, document-oriented database. Written in C++, MongoDB features:

• Document-oriented storage (the simplicity and power of JSON-like data schemas)



• Dynamic queries



• Full index support, extending to inner-objects and embedded arrays



• Query profiling



• Fast, in-place updates



• Efficient storage of binary data large objects (e.g. photos and videos)



• Replication and fail-over support



• Auto-sharding for cloud-level scalability



• MapReduce for complex aggregation



• Commercial Support, Hosting, and Consulting

MongoDB bridges the gap between key-value stores (which are fast and highly scalable) and traditional RDBMS systems (which provide structured schemas and powerful queries).

- 索引方面

“Formally speaking, these indexes are implemented as "B-Tree" indexes.”

在索引方面，采用的还是B-Tree索引的，无法多索引做交集运算(intersect)，无法满足我的多字段组合查询的需求。

只能说符合了Schemaless, Key-Value store两个特点，加上基于索引的查询接口。

- 分布式架构

分布式特性、Replication、Fail-over、MapReduce这几个还是比较有价值的。