1.德比：
Derby是用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。它可以嵌入Java应用程序中，也可以用作数据库服务器。
2. CouchDB：
CouchDB是一个面向开源文档的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来存储数据，使用JavaScript作为其使用MapReduce的查询语言以及用于API的HTTP。它由Apache Software Foundation开发，最初于2005年发布。它是用Erlang编写的。
Derby和CouchDB之间的区别：
| 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. |