Python Tutorials · Python MySQL

MySQL Delete

Learn all about MySQL Delete in this comprehensive tutorial.

5 min read advanced

MySQL Order By

MySQL Drop Table

•You can delete records from an existing table by using the "DELETE FROM" statement:
•It is considered a good practice to escape the values of any query, also in delete statements.

Delete Record

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

python

import mysql.connectormydb = 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")

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

Note: 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:

python

import mysql.connectormydb = 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")

Module quiz

2 questions

Which of the following is true about MySQL Delete?

It is strictly typedIt is evaluated at runtimeIt requires explicit memory managementIt is deprecated

What is the most common pitfall when working with MySQL Delete?

SyntaxErrorIndentationErrorNameErrorTypeError

Answer all questions to submit.