Types of database?

1. Relational Database
2. NoSQL Database
3. Object-Oriented Database
4. Graph Database
5. Document-Oriented Database
6. Column-Family Database
7. In-memory Database
8. Distributed Database
9. Cloud Database
10. Time-Series Database

Relational Databases

- Store data in tables with rows and columns
- Enforce relationships between data using primary and foreign keys
- Examples: MySQL, PostgreSQL, Oracle

NoSQL Databases

- Store data in non-relational formats
- Designed for scalability and high performance
- Types include:
- Key-value stores (e.g., Redis, DynamoDB)
- Document stores (e.g., MongoDB, CouchDB)
- Graph databases (e.g., Neo4j, Titan)
- Time-series databases (e.g., InfluxDB, Prometheus)
- Wide-column stores (e.g., Cassandra, HBase)

In-memory Databases

- Store data in memory for faster access
- Trade off durability for performance
- Examples: Redis, Memcached

Object-Oriented Databases

- Store data as objects that encapsulate data and behavior
- Focus on modeling real-world entities and relationships
- Examples: Objectivity/DB, GemStone/S

Hierarchical Databases

- Store data in a tree-like structure where each node can have multiple child nodes
- Examples: IMS, VSAM

Network Databases

- Store data in a network-like structure where records are connected by links
- Focus on representing complex relationships between data
- Examples: CODASYL, IDMS

Multidimensional Databases

- Store data in a multidimensional array
- Designed for analyzing large amounts of data with multiple dimensions
- Examples: Oracle Hyperion Essbase, Microsoft Power BI

Distributed Databases

- Store data across multiple computers or geographical locations
- Designed for scalability and fault tolerance
- Examples: Spanner, CockroachDB