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[本文翻译的原始出处：厦门大学计算机系数据库实验室网站林子雨老师的云数据库技术资料专区https://dblab.xmu.edu.cn/topic/research/documentation/cloud_database]
云数据库比较
翻译：厦门大学计算机系林子雨(http://www.cs.xmu.edu.cn/linziyu) 翻译时间：2012年4月26日星期四
RDBaaS表示Relational Database as a Service。
ClouSE是为MYSQL设计的云存储引擎，可以利用类似Amazon S3等云存储为用户提供数据存储服务，ClouSE在云存储上提供了关系数据管理功能，可以支持事务和ACID。
数据安全性（Data confidentiality）：ClouSE是唯一能够在云计算环境中提供完整安全性的技术。为了保证云环境中数据的安全性，ClouSE在对数据进行存储之前，会采用军事级别的AES-256加密算法对数据进行加密。这就意味着，无论是数据传输过程，还是数据存储过程，数据的安全性都得到了可靠的保证，即使是数据存储服务供应商都无法看到这些数据。数据的安全性完全是由客户提供给ClouSE的密钥决定的。客户自己负责密钥的管理，可以完全控制谁可以访问这些数据。
快速的数据库访问：CloudSE可以和服务器应用程序（比如网页服务器）运行在同一个机器上，因此，这些服务器应用程序可以快速高效地访问数据库。其他的云数据库产品，都需要通过网络进行访问，因此，就必须重新设计服务器应用程序，从而来处理通过网络访问数据库可能出现的更长的时间延迟和更高的失败概率。许多服务器应用程序在设计时，都假设数据库访问是快速高效和可靠的。ClouSE完全支持这种假设。
ACID事务、二级索引和SQL：NoSQL服务不支持ACID事务、二级索引和结构化查询。ClouSE和RDBaaS都提供了很好的标准的关系数据库管理功能。
存储弹性：对于RDBaaS而言，一级存储的尺寸必须预先确定。用户必须为预留的存储空间付费，而不是为实际使用的存储空间付费。即使一些数据被删除了，也不会导致存储空间消耗的减小。对于CloudSE和NoSQL服务而言，存储空间的消耗是随着实际数据量动态增减的，用户只为自己实际使用的存储空间付费。
自动可扩展：在自动可扩展方面，我为ClouSE放置了一个黄色的“圆点”，表示ClouSE可以直接从云存储中获得可扩展性。对于一些负责管理大量内容（比如图片和视频）的应用而言，ClouSE可以获得优越的可扩展性。
Cloud Database Comparison
By Artem Livshits ⋅ March 13, 2012 ⋅Post a comment
Filed Under cloud computing, ClouSE, MySQL, S3
I went to a GSLUG meeting last Sat and gave a talk about ClouSE. The slides are mostly the same as here, with the addition of the cloud database technologies comparison chart:
RDBaaS stands for Relational Database as a Service.
Data confidentiality: ClouSE is the only cloud database technology that provides full data confidentiality in the cloud. To guarantee data confidentiality in the cloud ClouSE encrypts the data using military grade AES-256 encryption before it puts the data to the cloud storage. This ensures that the data is visible neither over the wire nor to the cloud storage provider. The data confidentiality is fully controlled with the encryption key that the customer provides to ClouSE. Customers are in charge of encryption key management and fully control who has access to their data, if anyone.
Fast DB access: ClouSE can run on the same machine as the server application (e.g. Web Server), so access from the server application to the database is fast and reliable. Other cloud databases need to be accessed over the Internet, so the server applications need to be re-designed to deal with longer response times and higher failure rates when accessing the database. Most server applications are designed to assume that database access is fast and reliable; ClouSE fully supports that assumption.
ACID transactions, Secondary indices, SQL: NoSQL services don’t support ACID transactions, secondary indices or structured queries. Both ClouSE and RDBaaS provide standard, well-known and widely used relational database management.
Storage elasticity: With RDBaaS, the primary storage size needs to be specified upfront. Users are charged for reserved storage, not for used storage. The storage consumption cannot shrink even if some of the data is deleted. With ClouSE and NoSQL services, the storage consumption grows and shrinks with the amount data, users pay only for storage they use.
Automatic scale out: I put a yellow dot for the automatic scale out for ClouSE to reflect its ability to scale out content delivery from cloud storage directly. Applications that manage a lot of content (e.g. images, videos) may achieve significant scale-out.