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Python MySQL Delete From By


Delete Record

You can delete records from an existing table by using the "DELETE FROM" statement:

Example

Delete any record where the address is "Mountain 21":

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")
Run example »

Important!: Notice the statement: mydb.commit(). It is required to make the changes, otherwise no changes are made to the table.

Notice the WHERE clause in the DELETE syntax: The WHERE clause specifies which record(s) that should be deleted. If you omit the WHERE clause, all records will be deleted!


Prevent SQL Injection

It is considered a good practice to escape the values of any query, also in delete statements.

This is to prevent SQL injections, which is a common web hacking technique to destroy or misuse your database.

The mysql.connector module uses the placeholder %s to escape values in the delete statement:

Example

Escape values by using the placeholder %s method:

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")
Run example »