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How to remove all of the data in a table using Django
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Inside a manager:
def delete_everything(self):
Reporter.objects.all().delete()
def drop_table(self):
cursor = connection.cursor()
table_name = self.model._meta.db_table
sql = "DROP TABLE %s;" % (table_name, )
cursor.execute(sql)
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Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...
How to modify a global variable within a function in bash?
...alise that if you just run the function without assigning it to a variable all the global variables within it will update. Instead of returning a string array, why not just update the string array in the function then assign it to another variable after the function has finished ?
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Correct owner/group/permissions for Apache 2 site files/folders under Mac OS X?
...go-rwx DIR (nobody other than owner can access content)
chmod go+x DIR (to allow "users" including _www to "enter" the dir)
sudo chgrp -R _www ~/my/web/root (all web content is now group _www)
chmod -R go-rwx ~/my/web/root (nobody other than owner can access web content)
chmod -R g+rx ~/my/web/root...
What is the most effective way for float and double comparison?
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Be extremely careful using any of the other suggestions. It all depends on context.
I have spent a long time tracing a bugs in a system that presumed a==b if |a-b|<epsilon. The underlying problems were:
The implicit presumption in an algorithm that if a==b and b==c then a==c.
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Logging uncaught exceptions in Python
... global type (much like using var self = this in Javascript). It doesn't really matter unless you need to access the type object inside your function, in which case you can use type_ as the argument instead.
– Ryan P
Jan 2 '13 at 17:08
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How to get current CPU and RAM usage in Python?
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Worked for me on OSX: $ pip install psutil; >>> import psutil; psutil.cpu_percent() and >>> psutil.virtual_memory() which returns a nice vmem object: vmem(total=8589934592L, available=4073336832L, percent=52.6, used=5022085120L, free=35602...
How can I get the client's IP address in ASP.NET MVC?
I'm totally new to the ASP.NET MVC stack, and I was wondering what happened to the simple Page object and the Request ServerVariables object?
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What optimizations can GHC be expected to perform reliably?
...has a lot of optimizations that it can perform, but I don't know what they all are, nor how likely they are to be performed and under what circumstances.
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How to make rpm auto install dependencies
...hip and filesystem permissions:
# chown -R root.root /home/user/repo
Install the createrepo package if not installed yet, and run
# createrepo /home/user/repo
# chmod -R o-w+r /home/user/repo
Create a repository configuration file, e.g. /etc/yum.repos.d/myrepo.repo containing
[local]
name=My Aw...