1.德比：
Derby 是一个用Java实现的功能齐全的开源关系数据库管理系统 (RDBMS)，顾名思义，它是由 Apache Software Foundations 开发的。它基于Java、JDBC 和 SQL 标准。 Derby 易于安装、部署和使用。它要么嵌入到Java应用程序中，要么用作数据库服务器。
2. 沙发数据库：
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。
Derby 和 CouchDB 的区别：
| SR.No. | Derby | Couchdb |
|---|---|---|
| 1 | It is developed by Apache Software Foundation in 1997. | It is developed by Apache Software Foundation in 2005. |
| 2 | It is written in Java language. | It is written in Erlang language. |
| 3 | The primary database model for Derby is Relational DBMS. | The primary database model for CouchDB is Document Store. |
| 4 | Server operating systems for Derby are Windows, macOs, Linux, Unix, BSD and z/OS. | CouchDB server operating systems are Android, BSD, Linux, OS X, Solaris and Windows. |
| 5 | APIs and other access methods used by Derby is JDBC. | APIs and other access methods used by CouchDB is RESTful HTTP/JSON API. |
| 6 | It support only Java programming language. | It supports C, C#, ColdFusion, Erlang, Java, JavaScript, PHP, PL/SQL, Python, Ruby, etc. |
| 7 | It support Master-Slave Replication methods. | It support Master-master replication, Master-slave replication. |
| 8 | In Derby, partitioning cannot be done. | In CouchDB, partitioning can be done by Sharding. |
| 9 | It is a open source software framework. | It is a open source software framework. |
| 10 | It support fine grained access rights according to SQL-standard. | It also support access right for users. |