Dotazy - agregované funkce - možné řešení

1. SELECT COUNT(*) FROM employees;
2. SELECT COUNT(*) FROM employees WHERE department_id=80;
3. SELECT COUNT(*) FROM departments;
4. SELECT COUNT(DISTINCT department_id) FROM employees;
5. SELECT AVG(salary), MAX(salary), MIN(salary), SUM(salary) FROM EMPLOYEES e, DEPARTMENTS d WHERE e.department_id=d.department_id AND d.department_name = 'IT';
6. SELECT AVG(salary), department_id FROM employees GROUP BY department_id;
7. SELECT department_id, AVG(salary) FROM employees HAVING AVG(salary) > 7000 GROUP BY department_id;
8. Pomocí vnořeného dotazu:

SELECT last_name, salary
FROM   employees
WHERE  salary =
              (SELECT max(salary)
               FROM   employees);

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