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add column to mysql table if it does not exist
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Note that INFORMATION_SCHEMA isn't supported in MySQL prior to 5.0. Nor are stored procedures supported prior to 5.0, so if you need to support MySQL 4.1, this solution isn't good.
One solution used by frameworks that use database migrations is...
What's the difference between dist-packages and site-packages?
... manager into this location:
/usr/lib/python2.7/dist-packages
Since easy_install and pip are installed from the package manager, they also use dist-packages, but they put packages here:
/usr/local/lib/python2.7/dist-packages
From the Debian Python Wiki:
dist-packages instead of site-packag...
How assignment works with Python list slice?
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Is a[:] = some_list equivalent to a = some_list[:] or a = some_list?
– jadkik94
May 17 '12 at 10:42
2
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Greenlet Vs. Threads
... can i use gevent in this case to read faster import hashlib def checksum_md5(filename): md5 = hashlib.md5() with open(filename,'rb') as f: for chunk in iter(lambda: f.read(8192), b''): md5.update(chunk) return md5.digest()
– Soumya
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Capture keyboardinterrupt in Python without try-except
...g.Event:
import signal
import sys
import time
import threading
def signal_handler(signal, frame):
print('You pressed Ctrl+C!')
sys.exit(0)
signal.signal(signal.SIGINT, signal_handler)
print('Press Ctrl+C')
forever = threading.Event()
forever.wait()
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What to put in a python module docstring? [closed]
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NAME
x - This module does blah blah.
FILE
/tmp/x.py
CLASSES
__builtin__.object
Blah
class Blah(__builtin__.object)
| This class does blah blah.
|
| Data and other attributes defined here:
|
| __dict__ = <dictproxy object>
| ...
Is it safe to push_back an element from the same vector?
If the second push_back causes a reallocation, the reference to the first integer in the vector will no longer be valid. So this isn't safe?
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Comparing mongoose _id and strings
...ls() method. With your example, results.userId.equals(AnotherMongoDocument._id). The ObjectID type also has a toString() method, if you wish to store a stringified version of the ObjectID in JSON format, or a cookie.
If you use ObjectID = require("mongodb").ObjectID (requires the mongodb-native lib...
Alternatives to JavaScript
...n target multiple languages so your code can be re-used in Java, C, Flash, PHP and Javascript programs. It offers type-safe and dynamic objects.
Opalang adds syntactic sugar to Javascript to provide direct database access, smart continuations, type-checking and assist with client/server separation....
Any reason not to use '+' to concatenate two strings?
...ucture, especially if it is growing. With list you can use list.extend(list_of_items) and list.append(item) which are much faster when concatenating stuff dynamically.
– Antti Haapala
Sep 11 '12 at 9:56
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