Pythonda ma'lumotlar bazasiga so'rovlar yuborish

Ma'lumotlar bazasiga ulanib bo'lingandan so'ng, unga so'rovlar yuborish mumkin. Buning uchun query o'zgaruvchisi ishlatiladi, unda users jadvalidan barcha ma'lumotlarni chiqarish uchun SQL so'rovi yoziladi. Ushbu o'zgaruvchi connection o'zgaruvchisi bo'lgan blokda yozilishi kerak:

try:
	with connect(
			host='localhost',
			user='root',
			password='',
			database='test',
	) as connection:
		query = "SELECT * FROM users"
		
	except Error as e:
	print(e)

Keyin, connection o'zgaruvchisida saqlanadigan MySQLConnection-obyekti bilan ishlash uchun yana bir with konstruktsiyasini yozamiz. Ushbu obyektga ketma-ket maxsus metodlar qo'llaniladi. Ularning birinchisi cursor metodi bo'lib, u MySQLConnection-obyektidan CMySQLCursor-obyektini yaratadi. Unga esa o'z navbatida execute metodi qo'llaniladi, u parametr sifatida uzatilgan SQL so'rovini bajarishni ta'minlaydi:

try:
	with connect(
		...
	) as connection:
		query = "SELECT * FROM users"
		with connection.cursor() as cursor:
			cursor.execute(query)

Keyin fetchall metodi yordamida barcha ma'lumotlarni olib chiqish va ularni result o'zgaruvchisiga yozish kerak. Olingan ma'lumotlarni chiqarish uchun esa ularni for tsikli orqali o'tkazish kerak:

try:
	with connect(
		...
	) as connection:
		query = "SELECT * FROM users"
		with connection.cursor() as cursor:
			cursor.execute(query)
			result = cursor.fetchall()
			
			for row in result:
				print(row)

To'liq kod quyidagicha ko'rinadi:

try:
with connect(
		host='localhost',
		user='root',
		password='',
		database='test',
) as connection:
	query = "SELECT * FROM users"
	with connection.cursor() as cursor:
		print(cursor)
		cursor.execute(query)
		result = cursor.fetchall()
		
		for row in result:
			print(row)
			
except Error as e:
print(e)

Kod bajarilgandan so'ng, konsolda barcha yozuvlar kortejlar ko'rinishida chiqadi:

(1, 'user1', 23, 400)
(2, 'user2', 25, 500)
(3, 'user3', 23, 500)
(4, 'user4', 30, 900)
(5, 'user5', 27, 500)
(6, 'user6', 28, 900)

users jadvalidan barcha ma'lumotlarni chiqaring.