What is the difference between WHERE and HAVING in SQL?

Short answer: WHERE: Filters rows before any grouping is done (i.e., filters individual records). HAVING: Filters records after grouping is done (i.e., filters grouped results).

Example code

SELECT department, AVG(salary) FROM employees GROUP BY department HAVING AVG(salary) > 50000; In this query, HAVING is used to filter groups that have an average salary greater than 50,000.

Real-world example (ShopNest)

ShopNest’s SQL Server database stores customers, products, and orders. Good indexes and clear foreign keys keep checkout queries fast and safe.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.