MySQL Connector/Python (RF variant)

Common errors

• ModuleNotFoundError: No module named 'mysql.connector'

  cause The `mysql-connector-python-rf` package or its official counterpart `mysql-connector-python` is not installed in the active Python environment.
  fix Ensure the correct package is installed: `pip install mysql-connector-python-rf` (though highly discouraged) or `pip install mysql-connector-python` (recommended).

• mysql.connector.errors.ProgrammingError: 1045 (28000): Access denied for user 'your_user'@'localhost' (using password: YES)

  cause Incorrect database user credentials (username or password) or insufficient privileges for the specified user.
  fix Verify the username, password, and host parameters in `mysql.connector.connect()`. Ensure the MySQL user has the necessary permissions on the target database.

• mysql.connector.errors.InterfaceError: 2003 (HY000): Can't connect to MySQL server on 'localhost:3306' (10061)

  cause The MySQL server is not running, is not accessible from the client machine, or the connection parameters (host, port) are incorrect.
  fix Check if the MySQL server is running and accessible. Verify the `host` and `port` parameters in the connection string. Ensure no firewall is blocking the connection.

• mysql.connector.errors.ProgrammingError: 1064 (42000): You have an error in your SQL syntax; check the manual...

  cause The SQL query being executed contains a syntax error or is malformed.
  fix Carefully review the SQL string passed to `cursor.execute()` for typos, incorrect keywords, or missing clauses. Use parameterized queries (`%s` placeholders) to prevent SQL injection and properly handle special characters.

Warnings

• breaking This library (`mysql-connector-python-rf`) is *abandoned and unmaintained*. Its last release was in February 2017, making it incompatible with modern Python versions and potentially containing unpatched security vulnerabilities.
  Fix: **DO NOT USE THIS PACKAGE.** Migrate immediately to the official and actively maintained `mysql-connector-python` (install via `pip install mysql-connector-python`).
• deprecated The package `mysql-connector-python-rf` was a temporary repackaging to resolve PyPI distribution issues of the official connector. It is severely outdated and not compatible with Python versions beyond 3.3.
  Fix: Use the official Oracle-maintained `mysql-connector-python` library. It offers full Python 3 compatibility and active development.
• gotcha Forgetting to call `connection.commit()` after executing DML (INSERT, UPDATE, DELETE) statements will result in changes not being saved to the database. This is a common DB-API 2.0 footgun.
  Fix: Always call `connection.commit()` after any operation that modifies the database (e.g., `cnx.commit()` in the quickstart). Alternatively, use a `with` statement for connections if the driver supports auto-commit or transaction management via context.

Install

• pip install mysql-connector-python-rf Install

Imports

• mysql.connector

  import mysql.connector

  This library was a repackaging of the official `mysql-connector-python` at the time, and therefore used the same `mysql.connector` import path.
• MySQLConnection

  from mysql.connector import MySQLConnection

  The core connection class, following DB-API 2.0 standards.

Quickstart

This quickstart demonstrates how to connect to a MySQL database, create a table, insert data, and query data using the `mysql.connector` module. It follows the standard Python DB-API 2.0 pattern and includes basic error handling and proper resource cleanup.

import mysql.connector
import os

host = os.environ.get('MYSQL_HOST', 'localhost')
user = os.environ.get('MYSQL_USER', 'your_user')
password = os.environ.get('MYSQL_PASSWORD', 'your_password')
database = os.environ.get('MYSQL_DATABASE', 'test_db')

try:
    # Establish a connection
    cnx = mysql.connector.connect(
        host=host,
        user=user,
        password=password,
        database=database
    )

    if cnx.is_connected():
        print("Successfully connected to MySQL database.")

        cursor = cnx.cursor()
        # Create a table (if it doesn't exist)
        cursor.execute("CREATE TABLE IF NOT EXISTS users (id INT AUTO_INCREMENT PRIMARY KEY, name VARCHAR(255), email VARCHAR(255))")
        cnx.commit()
        print("Table 'users' ensured to exist.")

        # Insert data
        add_user = ("INSERT INTO users (name, email) VALUES (%s, %s)")
        data_user = ("John Doe", "john.doe@example.com")
        cursor.execute(add_user, data_user)
        cnx.commit()
        print("Data inserted.")

        # Query data
        cursor.execute("SELECT id, name, email FROM users")
        for (id, name, email) in cursor:
            print(f"ID: {id}, Name: {name}, Email: {email}")

    else:
        print("Failed to connect to MySQL database.")

except mysql.connector.Error as err:
    print(f"Error: {err}")

finally:
    if 'cnx' in locals() and cnx.is_connected():
        cursor.close()
        cnx.close()
        print("MySQL connection closed.")