Difference between CouchDB and MySQL

1. CouchDB :
Apache CouchDB is an open-source document-oriented NoSQL database that uses multiple formats and protocols to store, transfer, and process its data, it uses JSON to store data, JavaScript as its query language using MapReduce, and HTTP for an API. It was developed by Apache Software Foundation and initially released in 2005. It is written in Erlang.

2. MySQL :
MySQL is an open-source relational database management system (RDBMS) based on Structured Query Language (SQL). It is developed and managed by oracle corporation and initially released on 23 may, 1995. It is widely being used in many small and large scale industrial applications and capable of handling a large volume of data.

Difference between CouchDB and MySQL :

S.NO.	CouchDB	MySQL
1.	Developed by Apache Software Foundation and initially released in 2005.	Developed by Oracle and released on May 1995.
2.	CouchDB is written in Erlang.	MySQL is written in C and C++.
3.	The primary database model for CouchDB is Document Store.	The primary database model for MySQL is Relational DBMS.
4.	In CouchDB there is no predefined datatypes.	MySQL have predefined datatypes such as float, date, number, etc.
5.	CouchDB is Data Schema free.	In MySQL Data Schema is fixed.
6.	CouchDB does not supports XML data format.	MySQL supports XML data format.
7.	CouchDB supports Map Reduce method.	MySQL does not supports Map Reduce method.
8.	CouchDB does not provides the concept of Referential Integrity. Hence, no Foreign Keys.	MySQL provides the concept of Referential Integrity and have Foreign keys.
9.	CouchDB does not supports ACID transactions.	MySQL provides ACID transactions.
10.	CouchDB provides Eventual Consistency method to ensure consistency in a distributed system.	MySQL provides Immediate Consistency method to ensure consistency in a distributed system.
11.	Server operating systems for CouchDB are Android, BSD, Linux, OS X, Solaris and Windows.	Server operating systems for MySQL are FreeBSD, Linux, OS X, Solaris, Windows.
12.	Famous companies like Akamai Technologies, Hothead Games, Inc., GenCorp Technologies, Vivint Solar, etc uses CouchDB.	Famous companies like Airbnb, Pinterest, Slack, Udemy, Twitter, etc uses MySQL.