1. MongoDB：
MongoDB 是一个开源的面向文档的数据库，用于大容量数据存储。它属于 NoSQL 数据库的分类。 NoSQL 工具意味着它不使用通常的行和列。 MongoDB 使用 BSON(文档存储格式)，它是 JSON 文档的二进制样式。
2. 亚马逊云搜索：
它是一种可扩展的基于云的搜索服务，是 Amazon Web Services 的一部分。它是亚马逊托管的搜索引擎服务，数据存储在亚马逊云中。该数据库支持 34 种语言，其特点是突出显示、自动完成和地理空间搜索。
MongoDB 和 Amazon CloudSearch 的区别：
| S.No.. | MongoDB | Amazon CloudSearch |
|---|---|---|
| 1. | It is developed By MongoDB, Inc in 2009. | It is developed By Amazon in 2012. |
| 2. | It is Open Source. | It is commercial. |
| 3. | Server operating systems for MongoDB is Linux, OS X, Solaris, Windows. | Server operating systems for Amazon CloudSearch is hosted. |
| 4. | Its Primary database model is a Document store. | Its primary database model is a Search engine. |
| 5. | It has predefined data type such as date or float. | It also has predefined data type such as date or float. |
| 6. | It supports read-only SQL queries via the MongoDB Connector for BI. | It does not support SQL. |
| 7. | APIs and other access methods for MongoDB is proprietary protocol using JSON. | APIs and other access methods for Amazon CloudSearch is HTTP API. |
| 8. | It is schema free. | It supports Data Schema. |
| 9. | It supports Server-side scripting using JavaScript. | It does not support Server-side scripting. |
| 10. | It supports Triggers. | It does not supports Triggers. |
| 11. | It supports Partitioning methods using Sharding. | It also supports Partitioning methods. |
| 12. | It does not provide the concept of Referential Integrity. Hence, there is no Foreign Keys. | It also does not provides the concept of Referential Integrity. Hence, there is no Foreign Keys. |
| 13. | It supports Multi-document ACID Transactions with snapshot isolation. | It does not support ACID properties. |