1. 卡桑德拉：
Cassandra 是一个免费、开源、分布式、广泛的列存储、NoSQL 数据库管理系统。它由 Apache 软件基金会开发，最初于 2008 年 7 月发布。Cassandra 旨在处理跨多个商用服务器的大量数据，提供高可用性且无单点故障。
2. MySQL：
MySQL 是一种基于结构化查询语言 (SQL) 的开源关系数据库管理系统 (RDBMS)。它由oracle 公司开发和管理，于1995 年5 月23 日首次发布。它被广泛应用于许多小型和大型工业应用程序，能够处理大量数据。
Cassandra 和 MySQL 的区别：
| S.NO. | Cassandra | MySQL | ||||||
|---|---|---|---|---|---|---|---|---|
| 1. | Developed by Apache Software foundation and released on July 2008. | Developed by Oracle and released on May 1995. | ||||||
| 2. | Cassandra is written only in Java language. | MySQL is written in C and C++ languages. | ||||||
| 3. | Cassandra is a NoSQL type database. | MySql is a RDBMS type database. | ||||||
| 4. | It does not provides ACID properties but can be tuned to support ACID properties. | MySQL provides ACID properties. | ||||||
| 5. | Read performance is highly efficient is Cassandra as it takes O(1) time. | MySQl requires reading from multiple tables using JOIN. Hence, to read it takes O(log(n)) time. | ||||||
| 6. | Writing performance in Cassandra is also very high and efficient. | Writing in MySQL requires a search first which slows down write performance. | ||||||
| 7. | Cassandra does not provides the concept of Referential Integrity. Hence no Foreign Keys. | MySQL provides the concept of Referential Integrity and have Foreign keys. | ||||||
| 8. | Cassandra provides Eventual Consistency and Immediate Consistency methods to ensure consistency in a distributed system. | MySQL only provides Immediate Consistency method to ensure consistency in a distributed system. | 9. | Server operating systems for Cassandra are BSD, Linux, OS X, Windows. | Server operating systems for MySQL are FreeBSD, Linux, OS X, Solaris, Windows. | 10. | Famous companies like Hulu, Instagram, Intuit, Netflix, Reddit, etc uses Cassandra. | Famous companies like Airbnb, Pinterest, Slack, Udemy, Twitter, etc uses MySQL. |