Post #2727

Now, let’s move to the next topic of SQL Roadmap: ✅HAVING Clause 🧠 1. What is HAVING? HAVING is used to filter grouped data 👉Think like this: - WHERE → filters rows (before grouping) - HAVING → filters groups (after grouping) ⚡ 2. WHERE vs HAVING Works on - WHERE: Rows - HAVING: Groups Used with - WHERE: SELECT - HAVING: GROUP BY Can use aggregates? - WHERE: ❌ No - HAVING: ✅ Yes 💡 3. Basic Syntax SELECT column, AGG_FUNCTION(column) FROM table_name GROUP BY column HAVING condition; 🎯 4. Examples (Very Important) 👉 Example 1: Departments with more than 2 employees SELECT department, COUNT() AS total_emp FROM employees GROUP BY department HAVING COUNT() > 2; 👉 Example 2: Departments with average salary > 50k SELECT department, AVG(salary) AS avg_salary FROM employees GROUP BY department HAVING AVG(salary) > 50000; ⚡ 5. WHERE + HAVING Together SELECT department, COUNT() AS total_emp FROM employees WHERE salary > 30000 GROUP BY department HAVING COUNT() > 2; 👉Step-by-step: 1. WHERE → filters employees with salary > 30k 2. GROUP BY → groups by department 3. HAVING → keeps only groups with > 2 employees 🎯 6. Practice Tasks 1. Find departments having more than 3 employees 2. Find departments with average salary > 60k 3. Count employees per department where salary > 40k 4. Show departments with total salary > 1,00,000 5. Find departments with minimum salary > 30k ⚡ Mini Challenge 🔥 👉 Find departments having more than 2 employees AND avg salary > 50k Double Tap ❤️ For Practice Task Solution