Caching Is Easy. Cache Invalidation Is the Hard Part.
python
dev.to
Imagine you're building an e-commerce application. A user opens a product page. Instead of querying the database every time, you store the product details in Redis. The page loads faster, and your database has less work to do. Everything looks great. Then someone updates the product price from ₹999 to ₹1,199. The database has the correct price. But your application keeps showing ₹999. Nothing is broken in the database. Your API is responding. Redis is working exactly as expected. Yet the use