Which requirement would prompt you to consider choosing RDBMS over NoSQL?
A. Complicated joins
B. High availability
C. Flexible schema
D. Easy scalability
The correct answer and explanation is :
Correct Answer: A. Complicated joins
Explanation:
Relational Database Management Systems (RDBMS) are typically chosen over NoSQL databases when the application demands complex querying and relational integrity, particularly when complicated joins between multiple tables are required.
Why RDBMS for Complicated Joins?
RDBMSs, such as MySQL, PostgreSQL, and Oracle, are designed around a structured schema and enforce relationships through foreign keys and join operations. SQL, the query language used by RDBMS, is highly optimized for operations that involve joining multiple tables and retrieving related data efficiently.
For example, in an enterprise application involving orders, customers, products, and shipments, you might need to join several tables to generate a report. RDBMS handles such use cases effectively by ensuring:
- Data consistency and integrity through ACID properties.
- Optimized performance for multi-table join queries.
- Structured relationships through normalized schemas.
Why Not NoSQL?
NoSQL databases (like MongoDB, Cassandra, or Couchbase) excel in high availability, horizontal scalability, and flexible schemas, making them suitable for use cases like big data analytics, real-time applications, and content management systems.
However, most NoSQL databases do not support joins natively or only offer limited support via application-level logic or aggregation pipelines, which makes handling complex relationships cumbersome and potentially inefficient.
Summary of Other Options:
- B. High availability – Better suited for NoSQL (e.g., Cassandra offers high availability by design).
- C. Flexible schema – NoSQL databases are preferred when data structures change frequently.
- D. Easy scalability – NoSQL databases typically scale more easily across distributed systems.
Conclusion:
If your application requires complicated joins and strong relational consistency, RDBMS is the more appropriate choice due to its robust querying capabilities and relational data structure.