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PythonTips

Install MySQLdb connector on Mac OSX

To install the python/MySQL connector on Mac OS X follow the following tutorials:

http://www.tech-recipes.com/mac_system_administration_tips726.html∞: this one discuss of the developer tools we have to install.
http://antoniocangiano.com/2007/12/22/how-to-install-django-with-mysql-on-mac-os-x/∞: this one contains all the steps to follow once the developer tools are set up!

Cast

To cast to string type:

i=0

print str(i)

Length of an array

myArray=[]

len(myArray)

MySQL connection

You have to create a cursor to connect to the database.
The cursor is created with MySQLdb.connect.
Then in the cursor class, you have a couple of methods:

execute(): to execute a mysql query
rowcount(): will return the number of lines of your sql query
fetchall(): get all the results from your sql query
fetchone(): method used to move forward through the resultset

2 ways to create sql queries and execute them:

sqlInsert = "insert into servers set servername='%s',location='%s',purpose='%s',live='%s',coderelease='%s'" % (servername,location,purpose,live,coderelease)

cursor.execute(sqlInsert)

cursor.execute("insert into servers set servername='%s',location='%s',purpose='%s',live='%s',coderelease='%s'" , (servername,location,purpose,live,coderelease))

The 1st one being the neater!

methods definition

When defining your class methods, you must explicitly list self as the first argument for each method, including init

built in functions

http://docs.python.org/lib/built-in-funcs.html∞

Python Editor

SPE. To install it on mac, you need the python framework and wxpython: http://www.wxpython.org∞

If you want to change the way shortcut are bound on your keyboard please check this post: https://lists.berlios.de/pipermail/python-spe-dev/2005-December/000075.html∞
Basically, shortcuts are defined in Contents/Resources/_spe/shorcuts/OS.py

Not showing the password

import getpass

password = getpass.getpass('Password: ')

Nested dictionaries

http://old.nabble.com/creating-a-nested-dictionary-td15061183.html∞

def deep_default_dict(level):

    """

    This has been done to implement dict with several depths. 

    http://old.nabble.com/creating-a-nested-dictionary-td15061183.html

    """

    if level < 1:

        raise ValueError()

    result = dict

    while level > 1:

        result = lambda: defaultdict(result)

        level -= 1

    return result

To do so, we need to juggle with default dictionary

Interaction with JMS / ApacheMQ

https://twiki.cern.ch/twiki/bin/view/EGEE/MsgTutorial#Setting_message_expiration∞