Difference of Relational and Non-relational Databases
| Aspect | Relational Databases | Non-Relational Databases |
|---|---|---|
| Data Structure | Structured, tabular format with predefined schemas | Various data models (document-oriented, key-value, etc.) |
| Organized into tables, rows, and columns | Flexible data storage, dynamic schemas | |
| Follows the relational model principles | May not enforce a fixed structure | |
| Schema | Enforces a fixed schema | Typically schema-less or schema-flexible |
| Changes may require altering tables | Dynamic addition of fields without affecting data | |
| Scalability | Primarily scales vertically | Designed for horizontal scalability |
| Adds more resources to a single server | Distributes data across multiple nodes or servers | |
| Use Cases | Well-suited for well-defined data structures | Ideal for dynamic or evolving data structures |
| Common in business applications, finance, etc. | Suited for unstructured or semi-structured data | |
| Query Language | Uses SQL for querying and manipulating data | Query languages vary (e.g., MongoDB uses JSON-like) |
| Standardized language for relational databases | No standardized query language for all types | |
| Complexity & Dev Speed | Can be more complex to design and maintain | Offers flexibility and speed in development |
| Schema changes may require careful planning | Well-suited for agile development processes | |
| Examples | MySQL, PostgreSQL, Oracle Database, SQL Server | MongoDB (document-oriented), Redis (key-value), etc. |