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”)
Output:
C:\Users\My Name>python demo_mysql_delete.py
1 record(s) deleted
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”)
Output:
C:\Users\My Name>python demo_mysql_delete_escape.py
1 record(s) deleted