Cloud Computing - Proposal 云服务器上多种类型数据库的性能比较和原理探究
题目：云服务器上多种类型数据库的性能比较和原理探究
我们选取了三种不同类型的数据库：Mysql、MongoDB、Redis 来测试它们在不同种类的云服务器上的读写性能、网络并发性能、存储性能、CPU占用率、事务处理能力以及安全性能方面的区别，并且结合数据库的底层实现原理来解释这种性能方面的区别。
其中
Mysql是一种关系型数据库。
关系型数据库是一种基于关系的数据库，而关系模型可通过二维表来进行表示，所以数据的存储方式是由行列组成的表，每一列是一个字段，每一行是一个记录。在关系型数据库中通常包含了三个概念：数据库（database）、表（table）、记录（record）。Mysql常用B+树进行索引。
Redis和MongoDB是非关系型数据库。
MongoDB是由c++语言编写的非关系型数据库，是一个基于分布式文件存储的开源数据库系统，其内容存储类似JSON对象，它的字段可以包含其他的文档、数组以及文档数组。MongoDB包含了三个层次概念：数据库（database）、集合（collection）、文档（document）。MongoDB的数据索引是B-树。
Redis是一种内存数据库，所有的数据都是放在内存之中，定期写入磁盘中，当内存不够的时候，可选择指定的LRU算法删除数据。Redis是基于哈希字典建立的，因此其索引方式是哈希。
在探究不同数据库性能上的区别的同时，我们也会结合各种数据库在不同种类云服务器上运行性能的区别，进行综合的分析。
Title: Performance Comparison and Principle Exploration of Various Types of Databases on Cloud Servers
We selected three different types of databases: Mysql, MongoDB, and Redis to test their differences in read and write performance on different types of cloud servers, network concurrency performance, storage performance, CPU usage, transaction processing capabilities, and security performance. And combined with the underlying implementation of the database to explain this performance difference.
Mysql is a relational database.
A relational database is a relational database, and a relational model can be represented by a two-dimensional table. Therefore, the data is stored in a table consisting of rows and columns. Each column is a field and each row is a record. Relational databases usually contain three concepts: database, table, and record. Mysql often uses B + trees for indexing.
Redis and MongoDB are non-relational databases.
MongoDB is a non-relational database written in the C ++ language. It is an open source database system based on distributed file storage. Its content store is similar to JSON objects, and its fields can contain other documents, arrays, and document arrays. MongoDB includes three levels of concepts: database, collection, and document. MongoDB's data index is a B-tree.
Redis is a kind of memory database. All data is stored in memory and written to disk periodically. When the memory is not enough, you can choose the specified LRU algorithm to delete the data. Redis is based on a hash dictionary, so its indexing method is hash.
While exploring the differences in the performance of different databases, we will also conduct a comprehensive analysis of the differences in the performance of various databases on different types of cloud servers.
相关参考：
数据库性能指标评估模型