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What is a Relational Database?

May 23, 2024
Explore how relational databases enhance system architecture, focusing on scalability and federation, with additional resources for deepening your understanding.
Relational databases (RDBMS) are pivotal in maintaining the persistence layer of an application, effectively serving as the system’s memory. They are renowned for their structured approach and robust transactional support, which makes them ideal for applications requiring reliable data integrity.
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Why Relational Databases are Essential

Logic operations and calculations are crucial for system functionality, but without a way to store these results, systems would lack utility and impact. Relational databases address this by providing a durable storage mechanism that not only holds data but also supports complex queries and relationships among the data.

Challenges in Scaling Relational Databases

Scaling relational databases involves several strategies, each with its own set of complexities:
  • Vertical Scaling: Increasing the capabilities of a single server, such as CPU, RAM, or storage, can temporarily accommodate larger loads. However, there are practical and economic limits to how far this can scale.
  • Horizontal Scaling: This approach involves adding more servers to distribute the load, often implemented through sharding or partitioning the data across multiple servers.
  • Federation: By segmenting data by function—for example, separating user data from product data—federation allows each database to handle less load and reduces the complexity of data management within each database.

Benefits of Relational Database Federation

Federation can be particularly effective in environments where different categories of data have varying usage patterns and scalability needs. This method reduces contention and improves performance by isolating database load to specific servers, making the management and scaling of data more feasible.

Visualizing Database Federation

In system diagrams, federation can be represented by multiple database icons, each labeled according to the function or feature it supports. This visualization helps stakeholders understand the distribution and scalability strategy of the database layer within the system.
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The strategic use of relational databases is crucial in building scalable, reliable, and efficient systems. By understanding and implementing appropriate scaling strategies like federation, system architects can ensure that their databases not only store data efficiently but also contribute to the overall performance and resilience of the system.

🎓 Additional Learning Resources