Difference between Couchbase and IBM Db2

1. Couchbase : Couchbase Server is an open-source, distributed, JSON document database that is enhanced for interactive applications. It is also known as Membase. It was developed by Couchbase, Inc. and initially released in August 2010. It is written using C++, Erlang, C, Go languages and its server is designed to provide us with easy-to-scale key-value or JSON document access with high sustained throughput and low latency. 2. IBM Db2 : IBM Db2 is a family of data management products, including database servers, developed by IBM. It is a Relational Database Management System (RDBMS) which supports object-oriented features and non relational structure with XML. Db2 is designed to store, analyze and retrieve the data efficiently. It was initially released in 1983 and is written in C, C++, Java and Assembly language.
Difference between Couchbase and IBM Db2 :

SR.NO	Couchbase	IBM Db2
1	It is developed by Couchbase, Inc. in 2010	It is developed by IBM in 1983.
2	It is written in C++, Erlang, C and Go languages.	It is written in C, C++, Assembly language, Java languages.
3	The primary database model for Couchbase is Document Store.	The primary database model for Db2 is Relational DBMS.
4	Server operating systems for Couchbase are Linux, OS X and Windows.	Server operating systems for Db2 are AIX, HP-UX, Linux, Solaris, Windows and z/OS.
5	It does not have the concept of Foreign keys.	It has the concept of Referential Integrity and Foreign keys.
6	It supports Map Reduce method.	It does not support of Map Reduce method.
7	Famous companies like Lockwood Publishing, Code Weavers, MSLGROUP, The Doyle Group, etc uses Couchbase.	Famous companies like JPMorgan Chase, Bank of America, Scotiabank, Citi, etc use Db2.
8	It has free Data Schema.	It has fixed Data Schema.