1. Redis :
Redis 代表远程字典服务器，它是一个内存数据结构项目，实现了具有可选持久性的分布式内存键值数据库。 Redis 由 Redis 实验室开发，最初于 2009 年 5 月 10 日发布。它是用 ANSI 和 C 语言编写的。 Redis 提供了内存效率、运行速度快、高可用性，并提供了一些特性，如持久性、复制、集群等。
2.IBM Db2：
Db2 是由 IBM 开发的一系列数据管理产品，包括数据库服务器。它是一个关系数据库管理系统 (RDBMS)，支持面向对象的特性和非关系结构的 XML。 Db2 旨在高效地存储、分析和检索数据。它最初于 1983 年发布，使用 C、C++、 Java和汇编语言编写。
Redis 和 IBM Db2 的区别：
| S.No. | REDIS | IBM Db2 |
|---|---|---|
| 1. | It was developed by Redis labs and initially released on May 10, 2009. | It was developed by IBM and initially released in 1983. |
| 2. | Redis is written in ANSI and C languages. | Db2 is written in C, C++, Assembly language, Java languages. |
| 3. | The primary database model for Redis is Key-Value Store. | The primary database model for Db2 is Relational DBMS. |
| 4. | The license for Redis is Open Source. | The license for Db2 is Commercial. |
| 5. | Redis is Data Schema Free. | In Db2 data schema is fixed. |
| 6. | Redis does not support XML data format. | Db2 supports XML data format. |
| 7. | Redis does not support SQL queries. | Db2 supports SQL. |
| 8. | Redis does not have the concept of Foreign keys. | Db2 has the concept of Referential Integrity and Foreign keys. |
| 9. | Redis does not have Triggers. | Db2 has Triggers. |
| 10. | Redis supports secondary indexes with RediSearch module only. | Db2 supports secondary indexes without any restrictions. |
| 11. | Server operating systems for Redis are BDS, Linux, OS X and Windows. | Server operating systems for Db2 are AIX, HP-UX, Linux, Solaris, Windows and z/OS. |
| 12. | Some companies like Twinkl Educational Publishing, Merrill Corporation, ASOS.com Limited, Owler, Inc., etc use Redis. | Some companies like JPMorgan Chase, Bank of America, Scotiabank, Citi, etc use Db2. |