1. 沙发数据库：
Apache CouchDB 是一个开源的面向文档的 NoSQL 数据库，它使用多种格式和协议来存储、传输和处理其数据，它使用 JSON 存储数据，使用 MapReduce 作为其查询语言的 JavaScript，以及用于 API 的 HTTP。它由 Apache 软件基金会开发，最初于 2005 年发布。它是用 Erlang 编写的。
2. 玛丽亚数据库：
MariaDB 是一个开源关系数据库管理系统 (RDBMS)，是广泛使用的 MySQL 数据库技术的兼容替代品。它由 MariaDB Foundation 开发并于 2009 年 10 月 29 日首次发布。MariaDB 具有大量新功能，这使其在性能和用户导向方面更加出色。
CouchDB 和 MariaDB 的区别：
| S.NO. | CouchDB | MariaDB |
|---|---|---|
| 1. | Developed by Apache Software Foundation and initially released in 2005. | Developed by MariaDB Foundation and initially released on 29 October 2009. |
| 2. | CouchDB is written in Erlang. | MariaDB is written in C, C++, Perl and Bash languages. |
| 3. | The primary database model for CouchDB is Document Store. | The primary database model for MariaDB is Relational DBMS. |
| 4. | In CouchDB there is no predefined datatypes. | MariaDB have predefined datatypes such as float, date, number, etc. |
| 5. | CouchDB does not supports XML data format. | MariaDB supports XML data format. |
| 6. | CouchDB is Data Schema free. | In MariaDB Data Schema supports Dynamic columns. |
| 7. | CouchDB supports Map Reduce method. | MariaDB does not supports Map Reduce method. |
| 8. | CouchDB does not provides the concept of Referential Integrity. Hence, no Foreign Keys. | MariaDB provides the concept of Referential Integrity and have Foreign keys. |
| 9. | CouchDB provides Eventual Consistency method to ensure consistency in a distributed system. | MariaDB provides Immediate Consistency method to ensure consistency in a distributed system. |
| 10. | CouchDB does not supports ACID transactions. | MariaDB provides ACID transactions. |
| 10. | Server operating systems for CouchDB are Android, BSD, Linux, OS X, Solaris and Windows | Server operating systems for MariaDB are FreeBSD, Linux, Solaris, Windows. |
| 12. | Famous companies like Akamai Technologies, Hothead Games, Inc., GenCorp Technologies, Vivint Solar, etc uses CouchDB. | Famous companies like CUNY, Accenture, Docplanner, Grooveshark, Northrop Grumman, uses MariaDB. |