MySQL for Python

Table of Contents

MySQL for Python

Credits

About the Author

About the Reviewers

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Errata

Piracy

Questions

1. Getting Up and Running with MySQL for Python

Getting MySQL for Python

Using a package manager (only on Linux)

Using RPMs and yum

Using RPMs and urpm

Using apt tools on Debian-like systems

Using an installer for Windows

Using an egg file

Installing egg handling software

Using a package manager (Linux)

Without a package manager (Mac, Linux)

On Microsoft Windows

Installing MySQL for Python from an egg file

Using a tarball (tar.gz file)

Importing MySQL for Python

Accessing online help when you need it

MySQLdb

_mysql

Connecting with a database

Creating a connection object

Creating a cursor object

Interacting with the database

Closing the connection

Multiple database connections

Summary

2. Simple Querying

A brief introduction to CRUD

Forming a query in MySQL

SELECT

* (asterisk)

FROM

staff

; (semicolon)

Other helpful quantifiers

WHERE

GROUP BY

HAVING

ORDER BY

LIMIT

INTO OUTFILE

Passing a query to MySQL

A simple SELECT statement

Modifying the results

Using user-defined variables

Determining characteristics of a database and its tables

Determining what tables exist

Assigning each table a number

Offering the options to the user

Allowing the user to detail a search query

Changing queries dynamically

Pattern matching in MySQL queries

Putting it into practice

Project: A command-line search utility

Preparing a database for searching

Planning your work, then working your plan

Develop a well-abstracted search functionality

Specifying the search term from the command-line

Implementing and incorporating the other functions: -t, -f, and -o

Including an option for an output file

Room to grow

Summary

3. Simple Insertion

Forming a MySQL insertion statement

INSERT

INTO

Table name

Column names

VALUES

; (semicolon)

Helpful ways to nuance an INSERT statement

INSERT...SELECT...

INSERT DELAYED…

INSERT...ON DUPLICATE KEY UPDATE...

Passing an insertion through MySQL for Python

Setting up the preliminaries

A simple INSERT statement

More complex INSERT commands

Using user-defined variables

Using metadata

Querying the database for its structure

Retrieving the table structure

Changing insertion values dynamically

Validating the value of name

Validating the value of price

Querying the user for a correction

Passing fish and price for validation

Essentials: close and commit

In need of some closure

What happened to commit?

Why are these essentials non-essential?

Project: A command-line insertion utility

The necessary modules

The main() thing

Coding the flag system

Testing the values passed by the user

Try to establish a database connection

Showing the tables

Showing the table structure, if desired

Accepting user input for the INSERT statement

Building the INSERT statement from the user input and executing it

Committing changes and closing the connection

Coding the other functions

valid_digit() and valid_string()

valid_table()

query()

Calling main()

Room to grow

Summary

4. Exception Handling

Why errors and warnings are good for you

Errors versus warnings: There's a big difference

The two main errors in MySQLdb

DatabaseError

InterfaceError

Warnings in MySQL for Python

Handling exceptions passed from MySQL

Python exception-handling

Catching an exception from MySQLdb

Raising an error or a warning

Making exceptions less intimidating

Catching different types of exceptions

Types of errors

DataError

IntegrityError

InternalError

NotSupportedError

OperationalError

ProgrammingError

Customizing for catching

Catching one type of exception

Catching different exceptions

Combined catching of exceptions

Raising different exceptions

Creating a feedback loop

Project: Bad apples

The preamble

Making the connection

Sending error messages

The statement class

The __init__ method

Storing the statement type

Forming the statement

Execute the MySQL statement

Handling any fallout

The main() thing

Try, try again

If all else fails

Room to grow

Summary

5. Results Record-by-Record

The problem

Why?

Computing resources

Local resources

Web applications

Network latency

Server-client communications

Apparent responsiveness

Pareto's Principle

How?

The fetchone() method

The fetchmany() method

Iteration: What is it?

Generating loops

while...if loops

The for loop

Iterators

Illustrative iteration

Iteration and MySQL for Python

Generators

Using fetchone() in a generator

Using fetchmany() in a generator

Project: A movie database

Getting Sakila

Creating the Sakila database

The structure of Sakila

Planning it out

The SQL statements to be used

Returning the films of an actor

Returning the actors of a film

Accepting user data

A MySQL query with class

The __init__ method: The consciousness of the class

Setting the query's type

Creating the cursor

Forming the query

Executing the query

Formatting the results

Formatting a sample

Formatting a larger set of results

The main() thing

Calling main()

Running it

Room to grow

Summary

6. Inserting Multiple Entries

The problem

Why not a MySQL script?

Lack of automation

Debugging the process

Inefficient I/O

Why not iterate?

A test sample: Generating primes

Comparing execution speeds

Introducing the executemany() method

executemany(): Basic syntax

executemany(): Multiple INSERT statements

executemany(): multiple SELECT statements

executemany(): Behind the scenes

MySQL server has gone away

Command-line option configuration

Using a configuration file

More than 16 MB is often unnecessary

Project: Converting a CSV file to a MySQL table

The preamble

The options

Defining the connection

Creating convert

The main() function

Calling main()

Room to grow

Summary

7. Creating and Dropping

Creating databases

Test first, create second

CREATE specifications

Specifying the default character set

Specifying the collation for a database

Declaring collation

Finding available character sets and collations

Removing or deleting databases

Avoiding errors

Preventing (illegal) access after a DROP

Creating tables

Covering our bases

Avoiding errors

Creating temporary tables

Dropping tables

Playing it safe

Avoiding errors

Removing user privileges

Doing it in Python

Creating databases with MySQLdb

Testing the output

Dynamically configuring the CREATE statement

Dropping databases with MySQLdb

Creating tables in Python

Verifying the creation of a table

Another way to verify table creation

Dropping tables with MySQLdb

Project: Web-based administration of MySQL

CGI vs PHP: What is the difference?

Basic CGI

Using PHP as a substitute for CGI

CGI versus PHP: When to use which?

Some general considerations for this program

Program flow

The basic menu

Authorization details

Three operational sections of the dialogue

The variables

Planning the functions

Code of each function

Connecting without a database

Connecting with a database

Database action

Table action

Query action

execute()

The HTML output

Basic definition

The message attribute

Defining header()

Defining footer()

Defining body()

Defining page()

Getting the data

Using CGI

Using PHP

Defining main()

Room to grow

Summary

8. Creating Users and Granting Access

A word on security

Creating users in MySQL

Forcing the use of a password

Restricting the client's host

Creating users from Python

Removing users in MySQL

DROPping users in Python

GRANT access in MySQL

Important dynamics of GRANTing access

The GRANT statement in MySQL

Using REQUIREments of access

Using a WITH clause

Granting access in Python

Removing privileges in MySQL

Basic syntax

After using REVOKE, the user still has access!?

Using REVOKE in Python

Project: Web-based user administration

New options in the code

Adding the functions: CREATE and DROP

Adding CREATE and DROP to main()

Adding the functions: GRANT and REVOKE

Adding GRANT and REVOKE to main()

Test the program

New options on the page

Room to grow

Summary

9. Date and Time Values

Date and time data types in MySQL

DATETIME

Output format

Input formats

Input range

Using DATETIME in a CREATE statement

DATE

Output and Input formats

Input range

TIMESTAMP

Input of values

Range

Defaults, initialization, and updating

YEAR

Two-digit YEAR values

Four-digit YEAR values

Valid input

TIME

Format

Invalid values

Date and time types in Python

Date and time functions

NOW()

CURDATE()

CURTIME()

DATE()

DATE_SUB() and DATE_ADD()

DATEDIFF()

DATE_FORMAT()

EXTRACT()

TIME()

Project: Logging user activity

The log framework

The logger() function

Creating the database

Using the database

Creating the table

Forming the INSERT statement

Ensure logging occurs

Room to grow

Summary

10. Aggregate Functions and Clauses

Calculations in MySQL

COUNT()

SUM()

MAX()

MIN()

AVG()

The different kinds of average

Mean

Median

Mode

Trimming results

DISTINCT

GROUP_CONCAT()

Specifying the delimiter

Customizing the maximum length

Using GROUP_CONCAT() with DISTINCT

Server-side sorting in MySQL

GROUP BY

ORDER BY

Using a universal quantifier

Sorting alphabetically or from low-to-high

Reversing the alphabet or sorting high-to-low

Sorting with multiple keys

Putting it in Python

Project: Incorporating aggregate functions

Adding to qaction()

New variables

New statement formation

Revising main()

Setting up the options

Changing the HTML form

Summary

11. SELECT Alternatives

HAVING clause

WHERE versus HAVING: Syntax

WHERE versus HAVING: Aggregate functions

WHERE versus HAVING: Application

Subqueries

Unions

Joins

LEFT and RIGHT joins

OUTER joins

INNER joins

NATURAL joins

CROSS joins

Doing it in Python

Subqueries

Unions

Joins

Project: Implement HAVING

Revising the Python backend

Revising qaction()

Revising main()

Revising the options

Revising the HTML interface

Room to grow

Summary

12. String Functions

Preparing results before their return

CONCAT() function

SUBSTRING() or MID()

TRIM()

Basic syntax

Options

Alternatives

REPLACE()

INSERT()

REGEXP

Accessing and using index data

LENGTH()

INSTR() or LOCATE()

INSTR()

LOCATE()

Nuancing data

ROUND()

FORMAT()

UPPER()

LOWER()

Project: Creating your own functions

Hello()

Capitalise()

DELIMITER

The function definition

Calling the function

Defining the function in Python

Defining the function as a Python value

Sourcing the MySQL function as a Python module

Sourcing the function as MySQL code

Room to grow

Summary

13. Showing MySQL Metadata

MySQL's system environment

ENGINE

The most popular engines

Transactions

Specifying the engine

ENGINE status

SHOW ENGINES

Profiling

SHOW PROFILE

SHOW PROFILES

SHOW system variables

Accessing database metadata

DATABASES

Using the USE command

Accessing metadata about tables

SHOW TABLES

SHOW TABLE STATUS

Showing columns from a table

FUNCTION STATUS

CREATE (DATABASE/FUNCTION/PROCEDURE/TABLE/VIEW)

Accessing user metadata

SHOW GRANTS

PRIVILEGES

Project: Building a database class

Writing the class

Defining fetchquery() and some core methods

Retrieving table status and structure

Retrieving the CREATE statements

Define main()—part 1

Writing resproc()

Define main()—part 2

The preamble

Modules and variables

Login and USE

Closing out the program

Room to grow

Summary

14. Disaster Recovery

Every database needs a backup plan

Offline backups

Live backups

Choosing a backup method

Copying the table files

Locking and flushing

LOCK TABLES

FLUSH

Unlocking the tables

Restoring the data

Delimited backups within MySQL

Using SELECT INTO OUTFILE to export data

Using LOAD DATA INFILE to import data

Archiving from the command line

mysqldump

Viewing the backup file

Other options

Restoring the data

mysqlhotcopy

Backing up a database with Python

Summary

Index

MySQL for Python

MySQL for Python

Copyright © 2010 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: September 2010

Production Reference: 1160910

Published by Packt Publishing Ltd.

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ISBN 978-1-849510-18-9

www.packtpub.com

Cover Image by Vinayak Chittar (<[email protected]>)

Credits

Author

Albert Lukaszewski

Reviewers

Swaroop C H

Andy Dustman

Geert JM Vanderkelen

Acquisition Editor

Steven Wilding

Development Editor

Wilson D'souza

Technical Editors

Prashant Macha

Charumati Shankaran

Indexer

Hemangini Bari

Editorial Team Leader

Aanchal Kumar

Project Team Leader

Priya Mukherji

Project Coordinator

Prasad Rai

Proofreader

Aaron Nash

Production Coordinator

Shantanu Zagade

Cover Work

Shantanu Zagade

About the Author

Albert Lukaszewski is principal consultant for Lukaszewski Consulting Services in southeast Scotland. He has programmed computers for 30 years. Much of his experience has related to text processing, database systems, and Natural Language processing (NLP). Currently he consults on database applications for companies in the financial and publishing industries.

In addition to MySQL for Python, Albert Lukaszewski has also written About Python, a column for the New York Times subsidiary, About.com.

Many people had a hand in this work beyond my typing at the keyboard. Some contributed by their effort and others by their sacrifice. Thanks to the team at Packt for their consistent understanding and support. I am particularly thankful to Steven Wilding for help and support above and beyond the call of duty.

Thanks also to Andy Dustman, Geert Vanderkelen, and Swaroop for their helpful review of this book and for making so many significant and helpful recommendations. This book would be much the poorer were it not for their suggestions.

To Richard Goodrich, who first introduced me to Python, thank you for liberating me from bondage to that other P-language. Funny what a little problem can lead to.

My heartfelt thanks and appreciation go to my wife, Michelle, and my sons, Cyrus and Jacob. The latter was born during the writing of this book and consistently brightens even the darkest Scottish weather with his smile. I appreciate your sacrifice. I could not have written this book without your support.

Finally, my thanks to my brother, Larry, who first introduced me to the world of computing. I would probably not know anything about computer programming if you had not left me your TRS-80. So this is all your fault, and I am glad you did it.

About the Reviewers

Swaroop C H has previously worked at Yahoo! and Adobe, has co-founded a startup, has written two technical books (one of which is used as a text book in more than ten universities worldwide), writes a popular blog that has been consistently rated one of the top ten blogs in India, and is a marathoner. More details at http://www.swaroopch.com/about/.

He has written two technical books—A Byte of Python and A Byte of Vim—beginner books to Python and Vim respectively. They are freely available under the Creative Commons license on his website www.swaroopch.com.

Andy Dustman (http://profiles.google.com/farcepest) is the primary author of MySQLdb, the MySQL interface for Python.

The MySQL-Python project is supported and funded purely by volunteers and donations by the user community at (http://sourceforge.net/projects/mysql-python/).

Andy has been using Python since 1997, and currently works on Django applications (using MySQL, of course) when not doing system and network administration. In his spare time, he rides motorcycles.

I would like to thank Kyle VanderBeek, who has recently become a co-developer on MySQLdb, and has helped to push me a bit to get some things done. 12 years is a long time to be working on a project, and motivation is sometimes hard to come by.

Ed Landa, for taking a chance on a grad school dropout, and for giving me the opportunity to release MySQLdb under an open source license.

Laura Michaletz, who encourages me and somehow manages to make me feel like a superstar.

And my wife, Wendy, for being there for me for three decades.

Geert JM Vanderkelen is a member of the MySQL Support Team at Sun, a wholly-owned subsidiary of Oracle. He is based in Germany and has worked for MySQL AB since April, 2005. Before joining MySQL he worked as developer, DBA and SysAdmin for various companies in Belgium and Germany. Today Geert specializes in MySQL Cluster and works together with colleagues around the world to ensure continued support for both customers and community. Geert is also the maintainer of MySQL Connector/Python.

Preface

Python is a dynamic programming language, which is completely enterprise ready, owing largely to the variety of support modules that are available to extend its capabilities. In order to build productive and feature-rich Python applications, we need to use MySQL for Python, a module that provides database support to our applications.

This book demonstrates how to boost the productivity of your Python applications by integrating them with the MySQL database server, the world's most powerful open source database. It will teach you to access the data on your MySQL database server easily with Python's library for MySQL using a practical, hands-on approach. Leaving theory to the classroom, this book uses real-world code to solve real-world problems with real-world solutions.

The book starts by exploring the various means of installing MySQL for Python on different platforms and how to use simple database querying techniques to improve your programs. It then takes you through data insertion, data retrieval, and error-handling techniques to create robust programs. The book also covers automation of both database and user creation, and administration of access controls. As the book progresses, you will learn to use many more advanced features of Python for MySQL that facilitate effective administration of your database through Python. Every chapter is illustrated with a project that you can deploy in your own situation.

By the end of this book, you will know several techniques for interfacing your Python applications with MySQL effectively so that powerful database management through Python becomes easy to achieve and easy to maintain.

What this book covers

Chapter 1, Getting Up and Running with MySQL for Python, helps you to install MySQL for Python specific software, how to import modules into your programs, connecting to a database, accessing online help, and creating a MySQL cursor proxy within your Python program. It also covers how to close the database connection from Python and how to access multiple databases within one program.

Chapter 2, Simple Querying, helps you to form and pass a query to MySQL, to look at user-defined variables, how to determine characteristics of a database and its tables, and program a command-line search utility. It also looks at how to change queries dynamically, without user input.

Chapter 3, Simple Insertion, shows forming and passing an insertion to MySQL, to look at the user-defined variables in a MySQL insertion, passing metadata between databases, and changing insertion statements dynamically without user input.

Chapter 4, Exception Handling, discusses ways to handle errors and warnings that are passed from MySQL for Python and the differences between them. It also covers several types of errors supported by MySQL for Python, and how to handle them effectively.

Chapter 5, Results Record-by-Record, shows situations in which record-by-record retrieval is desirable, to use iteration to retrieve sets of records in smaller blocks and how to create iterators and generators in Python. It also helps you in using fetchone() and fetchmany().

Chapter 6, Inserting Multiple Entries, discusses how iteration can help us execute several individual INSERT statements rapidly, when to use or avoid executemany(), and throttling how much data is inserted at a time.

Chapter 7, Creating and Dropping, shows to create and delete both databases and tables in MySQL, to manage database instances with MySQL for Python, and to automate database and table creation.

Chapter 8, Creating Users and Granting Access, focuses on creating and removing users in MySQL, managing database privileges with MySQL for Python, automating user creation and removal, to GRANT and REVOKE privileges, and the conditions under which that can be done.

Chapter 9, Date and Time Values, discusses what data types MySQL supports for date and time, when to use which data type and in what format and range, and frequently used functions for handling matters of date and time.

Chapter 10, Aggregate Functions and Clauses, shows how MySQL saves us time and effort by pre-processing data, how to perform several calculations using MySQL's optimized algorithms, and to group and order returned data by column.

Chapter 11, SELECT Alternatives, discusses how to use HAVING clauses, how to create temporary subtables, subqueries and joins in Python, and the various ways to join tables.

Chapter 12, String Functions, shows how MySQL allows us to combine strings and return the single, resulting value, how to extract part of a string or the location of a part, thus saving on processing, and how to convert cases of results.

Chapter 13, Showing MySQL Metadata, discusses the several pieces of metadata about a given table that we can access, which system variables we can retrieve, and how to retrieve user privileges and the grants used to give them.

Chapter 14, Disaster Recovery, focuses on when to implement one of several kinds of database backup plans, what methods of backup and disaster recovery MySQL supports, and how to use Python to back up databases

What you need for this book

The content of this book is written against MySQL 5.5, Python 2.5.2, and MySQL for Python 1.2.2. Development of the examples was done with MySQL 5.0, but everything was confirmed against the 5.5 documentation. As for operating systems, any of the main three will do:  Microsoft Windows, Linux, or Mac. Any additional requirements of modules are discussed in the book as they come up.

Who this book is for

This book is meant for intermediate users of Python who want hassle-free access to their MySQL database through Python. If you are a Python programmer who wants database-support in your Python applications, then this book is for you. This book is a must-read for every focused user of the MySQL for Python library who wants real-world applications using this powerful combination of Python and MySQL.

Conventions

In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.

Code words in text are shown as follows: We can include other contexts through the use of the include directive.

A block of code is set as follows:

import MySQLdb

mydb = MySQLdb.connect(host = 'localhost',

                      user = 'skipper',

                      passwd = 'mysecret',

                      db = 'fish')

Any command-line input or output is written as follows:

>>> print results ((1L, 'tuna', Decimal('7.50')), (2L, 'bass', Decimal('6.75')), (3L, 'salmon', Decimal('9.50')), (4L, 'catfish', Decimal('5.00')),

New terms and important words are shown in bold. Words that you see on the screen, in menus or dialog boxes for example, appear in the text like this: clicking the Next button moves you to the next screen.

Reference to a particular section or chapter are shown in italics.

Note

Warnings or important notes appear in a box like this.

Tip

Tips and tricks appear like this.

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If there is a topic that you have expertise in and you are interested in either writing or contributing to a book on, see our author guide on www.packtpub.com/authors.

Customer support

Now that you are the proud owner of a Packt book, we have a number of things to help you to get the most from your purchase.

Errata

Note

Downloading the example code for this book

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We appreciate your help in protecting our authors, and our ability to bring you valuable content.

Questions

You can contact us at <[email protected]> if you are having a problem with any aspect of the book, and we will do our best to address it.

Chapter 1. Getting Up and Running with MySQL for Python

It may seem rather unnecessary to start a book on MySQL for Python with a chapter on setting it up. There are, in fact, several ways to get MySQL for Python in a place such that your local Python installation can use it. Which one you use will depend as much on your familiarity with your operating system and with Python itself, as it will on which operating system and version of Python you are running.

In this chapter we will cover the following:

Where you can get MySQL for Python

Installing MySQL for Python

Importing the module into your programs

Accessing online help about the MySQL for Python API and its accompanying modules

How to connect to a database

How to create a MySQL cursor proxy within your Python program

How to close the database connection from Python

How to access multiple databases within one program

Getting MySQL for Python

How you get MySQL for Python depends on your operating system and the level of authorization you have on it. In the following subsections, we walk through the common operating systems and see how to get MySQL for Python on each.

Using a package manager (only on Linux)

Package managers are used regularly on Linux, but none come by default with Macintosh and Windows installations. So users of those systems can skip this section.

A package manager takes care of downloading, unpacking, installing, and configuring new software for you. In order to use one to install software on your Linux installation, you will need administrative privileges.

Administrative privileges on a Linux system can be obtained legitimately in one of the following three ways:

Log into the system as the root user (not recommended)

Switch user to the root user using su

Use sudo to execute a single command as the root user

The first two require knowledge of the root user's password. Logging into a system directly as the root user is not recommended due to the fact that there is no indication in the system logs as to who used the root account. Logging in as a normal user and then switching to root using su is better because it keeps an account of who did what on the machine and when. Either way, if you access the root account, you must be very careful because small mistakes can have major consequences. Unlike other operating systems, Linux assumes that you know what you are doing if you access the root account and will not stop you from going so far as deleting every file on the hard drive.

Unless you are familiar with Linux system administration, it is far better, safer, and more secure to prefix the sudo command to the package manager call. This will give you the benefit of restricting use of administrator-level authority to a single command. The chances of catastrophic mistakes are therefore mitigated to a great degree.

Tip

More information on any of these commands is available by prefacing either man or info before any of the preceding commands (su, sudo).

Which package manager you use depends on which of the two mainstream package management systems your distribution uses. Users of RedHat or Fedora, SUSE, or Mandriva will use the RPM Package Manager (RPM) system. Users of Debian, Ubuntu, and other Debian-derivatives will use the apt suite of tools available for Debian installations. Each package is discussed in the following:

Using RPMs and yum

If you use SUSE, RedHat, or Fedora, the operating system comes with the yum package manager. You can see if MySQLdb is known to the system by running a search (here using sudo):

sudo yum search mysqldb

If yum returns a hit, you can then install MySQL for Python with the following command:

sudo yum install mysqldb

Using RPMs and urpm

If you use Mandriva, you will need to use the urpm package manager in a similar fashion. To search use urpmq:

sudo urpmq mysqldb

And to install use urpmi:

sudo urpmi mysqldb

Using apt tools on Debian-like systems

Whether you run a version of Ubuntu, Xandros, or Debian, you will have access to aptitude, the default Debian package manager. Using sudo we can search for MySQLdb in the apt sources using the following command:

sudo aptitude search mysqldb

On most Debian-based distributions, MySQL for Python is listed as python-mysqldb.

Once you have found how apt references MySQL for Python, you can install it using the following code:

sudo aptitude install python-mysqldb

Using a package manager automates the entire process so you can move to the section Importing MySQL for Python.

Using an installer for Windows

Windows users will need to use the older 1.2.2 version of MySQL for Python. Using a web browser, go to the following link:

http://sourceforge.net/projects/mysql-python/files/

This page offers a listing of all available files for all platforms. At the end of the file listing, find mysql-python and click on it. The listing will unfold to show folders containing versions of MySQL for Python back to 0.9.1. The version we want is 1.2.2.

Note

Windows binaries do not currently exist for the 1.2.3 version of MySQL for Python. To get them, you would need to install a C compiler on your Windows installation and compile the binary from source.

This is outside the purpose of the present book, but tips for how to do this are contained in the README file that accompanies the 1.2.3 version.

Click on 1.2.2 and unfold the file listing. As you will see, the Windows binaries are differentiated by Python version—both 2.4 and 2.5 are supported. Choose the one that matches your Python installation and download it. Note that all available binaries are for 32-bit Windows installations, not 64-bit.

After downloading the binary, installation is a simple matter of double-clicking the installation EXE file and following the dialogue. Once the installation is complete, the module is ready for use. So go to the section Importing MySQL for Python.

Using an egg file

One of the easiest ways to obtain MySQL for Python is as an egg file, and it is best to use one of those files if you can. Several advantages can be gained from working with egg files such as:

They can include metadata about the package, including its dependencies

They allow for the use of egg-aware software, a helpful level of abstraction

Eggs can, technically, be placed on the Python executable path and used without unpacking

They save the user from installing packages for which they do not have the appropriate version of software

They are so portable that they can be used to extend the functionality of third-party applications

Installing egg handling software

One of the best known egg utilities—Easy Install, is available from the PEAK Developers' Center at http://peak.telecommunity.com/DevCenter/EasyInstall. How you install it depends on your operating system and whether you have package management software available. In the following section, we look at several ways to install Easy Install on the most common systems.

Using a package manager (Linux)

On Ubuntu you can try the following to install the easy_install tool (if not available already):

shell> sudo aptitude install python-setuptools

On RedHat or CentOS you can try using the yum package manager:

shell> sudo yum install python-setuptools

On Mandriva use urpmi:

shell> sudo urpmi python-setuptools

You must have administrator privileges to do the installations just mentioned.

Without a package manager (Mac, Linux)

If you do not have access to a Linux package manager, but nonetheless have a Unix variant as your operating system (for example, Mac OS X), you can install Python's setuptools manually. Go to:

http://pypi.python.org/pypi/setuptools#files

Download the relevant egg file for your Python version.

When the file is downloaded, open a terminal and change to the download directory. From there you can run the egg file as a shell script. For Python 2.5, the command would look like this:

sh setuptools-0.6c11-py2.5.egg

This will install several files, but the most important one for our purposes is easy_install, usually located in /usr/bin.

On Microsoft Windows

On Windows, one can download the setuptools suite from the following URL:

http://pypi.python.org/pypi/setuptools#files

From the list located there, select the most appropriate Windows executable file.

Once the download is completed, double-click the installation file and proceed through the dialogue. The installation process will set up several programs, but the one important for our purposes is easy_install.exe. Where this is located will differ by installation and may require using the search function from the Start Menu.

On 64-bit Windows, for example, it may be in the Program Files (x86) directory. If in doubt, do a search. On Windows XP with Python 2.5, it is located here:

C:\Python25\Scripts\easy_install.exe

Note that you may need administrator privileges to perform this installation. Otherwise, you will need to install the software for your own use. Depending on the setup of your system, this may not always work.

Installing software on Windows for your own use requires the following steps:

Copy the setuptools installation file to your Desktop.

Right-click on it and choose the runas option.

Enter the name of the user who has enough rights to install it (presumably yourself).

After the software has been installed, ensure that you know the location of the easy_install.exe file. You will need it to install MySQL for Python.

Installing MySQL for Python from an egg file

After installing EasyInstall, you still need to install the MySQL for Python egg. The egg files for MySQL for Python can be downloaded from the following URL:

http://sourceforge.net/projects/mysql-python/files/

There you will see a list of all available files relevant to MySQL for Python.

Which one you use depends on your operating system and your installed Python version. Currently, the only egg files available for MySQL for Python version 1.2.3c1 are for Linux running either Python 2.5 or 2.6. Mac users should use a tarball (tar.gz) file as discussed in the next section.

To get an egg file for Windows, click on the MySQL-python directory and select the 1.2.2 version. This is the same directory used for the Windows binaries discussed earlier in this chapter. This time, however, you need to select an egg for Windows that fits either Python 2.4 or 2.5. There is no 2.6 version.

Once you have the egg file for MySQL for Python, you simply need to invoke EasyInstall over the newly-downloaded egg file. How you do that will depend on the permissions you have for your operating system.

With administrator permissions, you can simply call the EasyInstall binary. For Linux, it will look like this:

shell> easy_install

For Windows, you will use a command similar to this one:

C:\Python25\Scripts\easy_install.exe

Note that you must have administrator privileges to do this. Otherwise, Windows users will have to install the software locally. Linux users can use sudo.

EasyInstall will then unpack the archive, install it in your default Python installation folders, and configure it for immediate use.

For Windows users, if you had to install setuptools locally, you may also require a local installation of Python itself in order to install MySQL for Python. See the section On Microsoft Windows under Installing egg-handling software, for help with this. If you need to go through this process, all of your configurations will be local, so you are best to use