1.甲骨文：
Oracle是一个关系数据库管理系统(RDBMS)。它由Oracle Corporation在1980年开发。它是第一个为网格计算而设计的数据库，它提供了最灵活，最具成本效益的方式来管理信息和应用程序。它可以在Windows，Unix，Linux和macOS等主要平台上运行。它是一个关系数据库，用户可以通过该数据库通过应用程序或称为SQL的查询语言来访问数据。
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。 Oracle和CouchDB之间的区别：
| S.NO. | ORACLE | COUCHDB |
|---|---|---|
| 1. | It was developed by Oracle Corporation in 1980. | It was developed by Apache Software Foundation in 2005. |
| 2. | It is written in C and C++. | It is written in Erlang language. |
| 3. | It is a commercial software. | It is an open-source software. |
| 4. | The primary database model for Oracle is Relational DBMS. | The primary database model for CouchDB is Document Store. |
| 5. | It uses Horizontal partitioning method for storing different data on different nodes. | It uses Sharding partitioning method for storing different data on different nodes. |
| 6. | The replication methods that Oracle supports are Master-Slave Replication, Master-Master Replication. | The replication methods that CouchDB supports are also Master-Slave Replication, Master-Master Replication. |
| 7. | Server operating systems for Oracle are Solaris, Linux, OS X, Windows. | Server operating systems for CouchDB are Android, BSD, Linux, OS X, Solaris and Windows. |
| 8. | ACID properties of transaction are used. | It does not provides ACID transactions. |
| 9. | Immediate Consistency method ensures consistency. | Eventual Consistency method ensures consistency in a distributed system. |
| 10. | It provides fine grained access rights according to SQL-standard. | It provides access rights for users can be defined per database. |