MySQL DELETE
Yozuvni o‘chirish
"DELETE FROM" iborasidan foydalanib, mavjud jadvaldagi yozuvlarni o‘chirishingiz mumkin:
Misol
Manzil "Mountain 21" bo‘lgan har qanday yozuvni o‘chiring:
import mysql.connector
mydb = mysql.connector.connect(
host="localhost",
user="yourusername",
password="yourpassword",
database="mydatabase"
)
mycursor = mydb.cursor()
sql = "DELETE FROM customers WHERE address = 'Mountain 21'"
mycursor.execute(sql)
mydb.commit()
print(mycursor.rowcount, "record(s) deleted")
Misolni ishga tushirish »
Muhim!: Operatorga e’tibor bering:mydb.commit(). O‘zgartirishlar kiritish talab qilinadi, aks holda jadvalga hech qanday o‘zgartirish kiritilmaydi.
DELETE sintaksisidagi WHERE bandiga e’tibor bering: WHERE bandi qaysi yozuv(lar) o‘chirilishi kerakligini belgilaydi. Agar siz WHERE bandini o‘tkazib yuborsangiz, barcha yozuvlar o‘chiriladi!
SQL in’ektsiyasini oldini olish
Har qanday so‘rovning qiymatlaridan qochish, shuningdek, o‘chirish iboralarida ham yaxshi amaliyot hisoblanadi.
Bu ma’lumotlar bazasini yo‘q qilish yoki noto‘g‘ri ishlatish uchun keng tarqalgan veb-xakerlik texnikasi bo‘lgan SQL in’ektsiyalarining oldini olishdir.
Mysql.connector moduli o‘chirish operatoridagi qiymatlardan qochish uchun %s to‘ldiruvchidan foydalanadi:
Misol
To‘ldiruvchi %s usuli yordamida qiymatlardan qochish:
import mysql.connector
mydb = mysql.connector.connect(
host="localhost",
user="yourusername",
password="yourpassword",
database="mydatabase"
)
mycursor = mydb.cursor()
sql = "DELETE FROM customers WHERE address = %s"
adr = ("Yellow Garden 2", )
mycursor.execute(sql, adr)
mydb.commit()
print(mycursor.rowcount, "record(s) deleted")
Misolni ishga tushirish »
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