MIN() and MAX() in PostgreSQL

The MIN() and MAX() functions in PostgreSQL return the smallest and largest values in a column, respectively.

1. Using MIN() to Find the Smallest Value

SELECT MIN(salary) FROM employees;

✅ Returns the lowest salary in the employees table.

2. Using MAX() to Find the Largest Value

SELECT MAX(salary) FROM employees;

✅ Returns the highest salary in the employees table.

3. Using MIN() and MAX() with a WHERE Condition

SELECT MIN(salary) FROM employees WHERE department = 'IT';

✅ Returns the lowest salary in the IT department.

SELECT MAX(salary) FROM employees WHERE department = 'Finance';

✅ Returns the highest salary in the Finance department.

4. Using MIN() and MAX() with GROUP BY

SELECT department, MIN(salary), MAX(salary) FROM employees GROUP BY department;

✅ Returns the lowest and highest salary for each department.

5. Using MIN() and MAX() with Dates

SELECT MIN(order_date) AS earliest_order, MAX(order_date) AS latest_order FROM orders;

✅ Returns the earliest and latest order dates.

6. Using MIN() and MAX() with HAVING

SELECT department, MAX(salary) FROM employees GROUP BY department HAVING MAX(salary) > 50000;

✅ Returns departments where the highest salary is greater than 50,000.