1. Neo4j ：
Neo4j 是最著名的图形数据库管理系统，它也是 Neo4j, Inc. 开发的 NoSQL 数据库系统。 Neo4j 与 Mysql 或 MongoDB 不同，因为它具有与其他数据库管理系统相比的特殊功能。 Neo4j 以图表的形式存储和呈现数据，而不是表格格式或 Jason 格式。在这里，整个数据由节点表示，在那里您可以创建节点之间的关系，这意味着整个数据库集合将看起来像一个图形，这使其与其他数据库管理系统不同。
2.沙发数据库：
CouchDB 是一个开源的面向文档的 NoSQL 数据库。它由 Apache 软件基金会开发，主要关注易用性。 Apache CouchDB 是最新的数据库品种之一。它是 2005 年发布的多主应用程序，并于 2008 年成为 Apache 项目。它使用多种格式和协议来存储、传输和处理其数据。它是用Erlang 编程语言编写的。
Neo4j 和 CouchDB 的区别：
| S.NO. | Neo4j | CouchDB |
|---|---|---|
| 1. | Developed by Neo4j, Inc. | Developed by Apache Software Foundation. |
| 2. | It was initially released in 2007. | It was initially released in 2005. |
| 3. | It is written using Java and Scala language. | It is written in Erlang. |
| 4. | Its server operating systems are Linux, OS X, Solaris, and Windows. | Its server operating systems are Android, BSD, Linux, OS X, Solaris and Windows. |
| 5. | Neo4j have predefined datatypes such as float, date, etc. | In CouchDB there is no predefined datatypes. |
| 6. | APIs and other access methods includes Bolt protocol, Cypher query language, Java API, Neo4j-OGM, RESTful HTTP, API, Spring Data Neo4j, TinkerPop 3. | APIs and other access methods include RESTful, HTTP/JSON API. |
| 7. | It is data schema free and schema optional. | It is only data schema free. |
| 8. | It supports Causal Clustering using Raft protocol Replication. | It supports both Master-Slave Replication and Master-Master Replication. |
| 9. | Its primary database model is is Graph DBMS. | Its primary database model is Document store. |
| 10. | It does not support Partitioning methods. | It supports Sharding Partitioning methods. |
| 11. | It does not supports MapReduce method. | It supports MapReduce method. |
| 12. | It supports ACID transactions. | It does not support ACID transactions. |
| 13. | It provides us with the concept of Referential Integrity and have Foreign keys. | It does not provide us with the concept of Referential Integrity. Hence, no Foreign Keys. |
| 14. | It provides Causal and Eventual Consistency configurable in Causal Cluster setup and Immediate Consistency in stand-alone mode in a disrtibution system. | It provides us with Eventual Consistency method to ensure consistency in a distributed system. |
| 15. | Famous companies like medium.com., Stack, Fiverr, Fundamentei, Trendyol Group, double slash, ingsmen Software, GAPO, etc uses Neo4j. | Famous companies like GenCorp Technologies, Akamai Technologies, Hothead Games, Inc., Vivint Solar, etc uses CouchDB. |
| 16. | Neo4j supports .Net, Clojure, Elixir, Go, Groovy, Haskell, Java, JavaScript, Perl, PHP, Python, Ruby, Scala programming languages. | Programming languages like C, C#, ColdFusion, Erlang, Haskell, Java, JavaScript, Lisp, Lua, Objective-C, OCaml, Perl, PHP, PL/SQL, Python, Ruby and Smalltalk is supported by CouchDB. |