Sizning SQL darajangiz qanday, qanday so'rovlar yozasiz?

Mening SQL darajam o'rta (middle). Men SELECT yordamida ma'lumotlarni olish uchun so'rovlar yozaman, ular filtrlash (WHERE), tartiblash (ORDER BY), jadvallarni birlashtirish (JOIN), agregatsiyalar (GROUP BY, HAVING), shuningdek, yangilash (UPDATE), qo'shish (INSERT) va o'chirish (DELETE) so'rovlarini o'z ichiga oladi. Ko'pincha tahlil uchun subso'rovlar va oynali funksiyalarni ishlataman. Masalan:

SELECT department, COUNT(*) AS employee_count
FROM employees
WHERE hire_date > '2020-01-01'
GROUP BY department
ORDER BY employee_count DESC;