1. Amazon DynamoDB：
Amazon DynamoDB是一个完全托管的数据库，同时支持文档和键值数据模型。功能如下–快速和灵活的NoSQL数据库服务，可为所有需要任何规模的一致，单位毫秒毫秒延迟的应用程序提供服务。它是Amazon提供的托管的，可扩展的数据库服务，其中的数据存储在Amazon云中。
2. Amazon SimpleDB：
它是Amazon托管的简单数据库服务，数据存储在Amazon Cloud中。它是Amazon是一项用于实时在结构化数据上运行查询的Web服务。该数据库由Amazon.com用Erlang编写。它具有以下功能–高可用性和灵活性，几乎没有管理负担。
Amazon DynamoDB和Amazon SimpleDB之间的区别：
| S.NO. | Amazon DynamoDB | Amazon SimpleDB |
|---|---|---|
| 1. | Developed By Amazon in 2012. | Developed By Amazon in 2007. |
| 2. | It is a hosted, scalable database service by Amazon with the data stored in the Amazon cloud. | It is a hosted simple database service by Amazon, with the data stored in the Amazon Cloud. |
| 3. | It supports the ACID property. | It does not support the ACID property. |
| 4. | It supports predefined data types such as float or date | It does not support predefined data types such as float or date |
| 5. | Its Primary database model is Document store and Key-value store. | Its primary database model is the Key-value store. |
| 6. | It does not offers an API for user-defined Map/Reduce methods. But maybe implemented via Amazon Elastic MapReduce (Amazon EMR). | It does not offer an API for user-defined Map/Reduce methods. |
| 7. | It supports sharding as a partitioning method. | It does not support partitioning methods. |
| 8. | It supports secondary indexes. | It also supports secondary indexes and all columns are indexed automatically. |
| 9. | The programming languages supported are .Net, ColdFusion, Erlang, Groovy, Java, JavaScript, Perl, PHP, Python, and Ruby. | The programming languages supported are .Net, C, Erlang, C++, Java, PHP, Python, Scala, and Ruby. |