NoSQL系列:选择合适的数据库
NoSQL系列:选择合适的数据库 为什么使用NoSQL数据库? 阻抗失衡 关系模型和内存中的数据结构不匹配 采用更为方便的数据交互方式提升开发效率 待处理的数据量很大 数据量超过关系型数据库的承载能力 大集群的出现 在成本方面,集群中应用关系数据库,许可费
NoSQL系列:选择合适的数据库
为什么使用NoSQL数据库?
-
阻抗失衡
关系模型和内存中的数据结构不匹配
采用更为方便的数据交互方式提升开发效率 -
待处理的数据量很大
数据量超过关系型数据库的承载能力
大集群的出现
在成本方面,集群中应用关系数据库,许可费用是一笔很大的支出;
横向扩展和纵向扩展:关系数据库一般只能是纵向扩展,通过对单机服务器的性能换代增强而实现;而对于扩展到多个服务器,
DBMS先天不足;(DBMS不是设计给集群使用的) -
对数据的访问效率要求高
NoSQL数据库的分类
键值数据库
-
产品
Redis
BerkerleyDB
Memcached
Project Voldemort
Riak
LevelDB -
适用场景
存放会话信息
用户配置信息
购物车数据 -
不适合的场景
数据间有大量关系
含有多项操作的事务
根据键值的部分来查询数据
操作关键字集合
文档数据库
-
产品
MongoDB
CouchDB
RavenDB
Terrastore
OrientDB -
适用场景
事件记录
内容管理系统及博客平台
网站分析及实时分析
电子商务应用程序
(需要较灵活的模式,低成本建立数据模型) -
不适合场景
包含多项操作的复杂查询
查询持续变化的聚合结构
列族数据库
-
产品
HBase
Amazon SimpleDB
Cassdndra
Hypertable
BigTable(google) -
适用场景
事件记录
(保存应用程序状态,运行中遇到的错误)
CMS及博客平台
计数器 -
不适用场景
需要ACID事务
查询模式变化频繁的场合
图数据库
-
产品
FlockDB
HyperGraphDB
Infinite Graph
Neo4J
OrientDB -
适用场景
互联数据
推荐引擎
基于位置的服务 -
不适用场景
更新全部或某个子集的实体
附思维导图
参考
《NoSQL精粹》
Posted by: 大CC | 07JUL,2014
博客:blog.me115.com [订阅]
微博:新浪微博

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