Difference between Neo4j and CouchDB

1. Neo4j :
Neo4j is the most famous graph database management system and it is also a NoSQL database system developed by Neo4j, Inc. Neo4j is different from Mysql or MongoDB as it has its features that’s makes it special compared to other Database Management System. Neo4j stores and present the data in the form of the graph not in tabular format or not in a Jason format. Here the whole data is represented by nodes and there you can create a relationship between nodes which means the whole database collection will look like a graph, which makes it unique from other database management system. 

2. CouchDB :
CouchDB is an open-source document-oriented NoSQL database. It was developed by the Apache software foundation and mainly focuses on ease of use. Apache CouchDB is one of the latest breeds of databases. It is a multi-master application released in 2005 and became an Apache project in 2008. It uses multiple formats and protocols to store, transfer, and process its data. It is written in the Erlang programming language.

Difference between Neo4j and CouchDB :

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 distribution 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.