A new major version of Connector/Python is available: v2.0.0 alpha has been been released and is available for download! As with any alpha-software, it’s probably not good to throw it in production just yet.

Our manual has the full change log but here’s an overview of most important changes for this relase.

Some incompatibilities

The world evolves, at least the software does, and Python is not different. I’m not as bold as the guys at Django who dropped support of Python v2.6 with the Django v1.7 release. I’m leaving it in because I’m nice.

Supported Python: 2.6 and 2.7 and 3.3 and 3.4

We do not support any longer Python 3.1 and 3.2. One of the reasons is that we consolidated the code bases for both major Python versions, and the unicode syntax brought back in 3.3 was a blessing (for example, u’パイソン’).

Raw Cursors Return bytearray Objects

Since we consolidated the code bases for Python 2 and 3, we needed make the behaviour as much as possible the same between the two. It’s not easy with Unicode strings, but with bytes we have the bytearray type. Raw cursors will return them instead of strings in Python 2 and bytes in Python 3.

If you want to have previous behaviour back, you can inherit from MySQLCursorRaw and change some methods. Please leave comments if you’d like an example for this.

LOAD LOCAL DATA INFILE  On by Default

In Connector/Python v1.x you needed to set the client flags to enable the LOAD LOCAL DATA INFILE on the client side. Here an example:

# Connector/Python v1.2
import mysql.connector
from mysql.connector import ClientFlag
cnx = mysql.connector.connect(.. , client_flags=[-ClientFlag.[LOCAL_FILES])

Now in Connector/Python v2.0 it is on. However, some people might not like it so there is a switch to disable it:

# Connector/Python v2.0
import mysql.connector
cnx = mysql.connector.connect(.. , allow_local_infile=False)

Note that you still need to make sure that the MySQL Server is configured to allow this statement.

New Cursors: dict and namedtuple

At last, we have cursors which return rows as dictionaries or named tuples. PEP-249 does not define these since not all database systems might return the columns in a case insensitive or sensitive way.

But this is MySQL.

Here is an example how to use cursor returning dictionaries:

query = (
    "SELECT TABLE_NAME, TABLE_ROWS "
    "FROM INFORMATION_SCHEMA.TABLES "
    " WHERE TABLE_SCHEMA='mysql' ORDER BY TABLE_NAME"
)
cur = cnx.cursor(dictionary=True)
cur.execute(query)
for row in cur:
    print("{TABLE_NAME:>30s} {TABLE_ROWS}".format(**row))

That’s far less code for something simple. Each row would look this:

    {u'TABLE_NAME': u'user', u'TABLE_ROWS': 11}

If you like named tuples better, you can do the same, simply giving the named_tuple argument.

cur = cnx.cursor(named_tuple=True)
cur.execute(query)
for row in cur:
    if row.TABLE_ROWS > 0:
        print("{name:>30s} {rows}".format(
            name=row.TABLE_NAME,
            rows=row.TABLE_ROWS))

You can also combine it with the raw=True argument to have raw cursors.

Options Files Support Added

Option files can now be read so you don’t have to have all these connection arguments repeated everywhere in your source code. There are lots of ways to do it this, but we needed to be able to read and support the MySQL options files read by client tools and server.

import mysql.connector
cnx = mysql.connector.connect(options_files='/etc/mysql/connectors.cnf')

By default we do not read any file. You have to explicitly specify which files and in which order have to be read. The options groups that are read are client and connector_python. You can also override this and specify which particular group(s) using the argument option_groups.

And more..

  • The  packaging and other supporting files have been removed. If you like to see WiX file (I dare you) for the Windows packaging, then you can (still) check the v1.x branches. We moved them away because these modules and files are (or can be) fixed and developed by other teams.
  • And watch out for v2.0.1 !

Useful links