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. 卡桑德拉：
Cassandra 是一个免费、开源、分布式、广泛的列存储、NoSQL 数据库管理系统。它由 Apache 软件基金会开发，最初于 2008 年 7 月发布。Cassandra 旨在处理跨多个商用服务器的大量数据，提供高可用性且无单点故障。
Derby 和 Cassandra 的区别：
| SR.NO. | Derby | Cassandra |
|---|---|---|
| 1 | It is developed by Apache Software Foundation in 1997. | It is also developed by Apache Software Foundation in 2008. |
| 2 | It is written in Java language. | It is written in Java language. |
| 3 | The primary database model for Derby is Relational DBMS. | The primary database model for Cassandra is Wide Column Store. |
| 4 | Server operating systems for Derby are Windows, macOs, Linux, Unix, BSD and z/OS. | Cassandra server operating systems are BSD, Linux, OS X, Windows. |
| 5 | It have the concept of Foreign keys. | It does not have the concept of Foreign keys. |
| 6 | It support only Java programming language. | It support C#, C++, Clojure, Erlang, Go, Haskell, Java, JavaScript info, Perl, PHP, Python, Ruby, Scala. |
| 7 | It support Master-Slave Replication methods. | It support selectable replication factor as replication methods. |
| 8 | APIs and other access methods used by Derby is JDBC. | APIs and other access methods used by Cassandra is Proprietary protocol, Thrift. |
| 9 | It is a open source software framework. | It is a open source software framework. |
| 10 | It supports fine grained access rights according to SQL-standard. | It supports access rights for users can be defined per object. |