SQL VS NoSQL

Here's a detailed explanation of when and why to use SQL and NoSQL, along with examples of their...

Here's a detailed explanation of when and why to use SQL and NoSQL, along with examples of their usage in companies like Flipkart, Uber, and Netflix:

When to Use SQL:

Structured Data:

Use SQL when your data has a well-defined schema, and relationships between entities are important.

Transactional Consistency:

SQL databases provide ACID (Atomicity, Consistency, Isolation, Durability) properties, which are essential for financial transactions or critical operations.

Relational Data:

Ideal for applications requiring complex joins or relational queries.

Long-Term Data Integrity:

SQL databases are suitable for systems where schema evolution is minimal, and strong data integrity is a priority.

Examples:

Flipkart:

SQL Use: Order processing, payments, inventory management.

SQL databases (e.g., MySQL or PostgreSQL) ensure consistent order processing and inventory updates across the system.

Uber:

SQL Use: User accounts, ride bookings, payment processing.

Uber uses SQL databases like PostgreSQL for maintaining transactional consistency during ride booking and fare calculations.

Netflix:

SQL Use: User subscriptions, billing, and metadata.

Netflix uses SQL for financial operations that require strict consistency.

When to Use NoSQL:

Scalability:

NoSQL databases are horizontally scalable, making them suitable for applications with rapidly growing datasets.

Unstructured/Semi-Structured Data:

Ideal for storing unstructured or semi-structured data like JSON, documents, or logs.

Real-Time Performance:

Low latency and high throughput for real-time applications.

Flexible Schema:

Schema-less nature allows easy adaptation to changes in data structure.

Examples:

Flipkart:

NoSQL Use: Product catalog, search, and recommendations.

Flipkart uses NoSQL databases like MongoDB or Cassandra to handle the massive scale of product data and enable fast search and filtering.

Uber:

NoSQL Use: Driver tracking, real-time location updates.

Uber uses Cassandra to store and query time-series data for tracking driver and rider locations in real time.

Netflix:

NoSQL Use: Movie catalog, streaming logs, recommendations.

Netflix uses Cassandra to handle the large-scale, globally distributed movie catalog and stream metadata.

Conclusion

Use SQL when:

_Data consistency and relational integrity are critical.

The workload is transactional and structured.

Use NoSQL when:

Scalability, high throughput, and flexible schemas are essential.

The workload involves unstructured or semi-structured data, or when handling real-time data .