1. 关系数据库：
RDBMS 代表关系数据库管理系统。它是最受欢迎的数据库。其中，数据以行的形式存储，即元组的形式。它包含许多表，数据可以很容易地访问，因为数据存储在表中。该模型由 EF Codd 提出。
2. NoSQL：
NoSQL 数据库代表非 SQL 数据库。 NoSQL 数据库不像关系数据库那样使用表来存储数据。它用于存储和获取数据库中的数据，一般用于存储大量数据。它支持查询语言并提供更好的性能。
关系型数据库和 NoSQL 的区别：
| Relational Database | NoSQL |
|---|---|
| It is used to handle data coming in low velocity. | It is used to handle data coming in high velocity. |
| It gives only read scalablity. | It gives both read and write scalablity. |
| It manages structured data. | It manages all type of data. |
| Data arrives from one or few locations. | Data arrives from many locations. |
| It supports complex transactions. | It supports simple transactions. |
| It has single point of failure. | No single point of failure. |
| It handles data in less volume. | It handles data in high volume. |
| Transactions written in one location. | Transactions written in many locations. |
| Deployed in vertical fashion. | Deployed in Horizontal fashion. |