| DATABASE | Read in the TOPIC |
|---|---|
| NoSQL (Not only SQL) | MongoDB |
| SQL (Structured Query Language) | PostgreSQL |
- Relational databases are organized using tables with predefined relationships between them. Data is stored in rows and columns, and the relationships between tables are defined using keys:
- Postgres SQL, MySQL, Oracle, and Microsoft SQL Server.
- NoSQL databases use a flexible schema and are designed to handle large amounts of unstructured data. They do not use tables, and instead store data in document, key-value, or graph formats:
- MongoDB, Cassandra, and Redis.
- Object-oriented databases are designed to store complex data types like objects and classes, and are often used in software development. They allow developers to store and manipulate data in an object-oriented way, and provide features like inheritance and encapsulation:
- db4o and ObjectStore.
- Hierarchical databases organize data in a tree-like structure, with each record having one parent and possibly many children. They are often used in mainframe environments:
- *IBM's Information Management System (IMS) and *the Windows Registry.