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MySQL CONCAT returns NULL if any field contain NULL
...es: it returns the first non-NULL value parameter passed to it (or NULL if all parameters are NULL). By passing an empty string as the second parameter, you are guaranteeing it will not return NULL.
– Jo.
Mar 10 '17 at 17:03
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How to capture stdout output from a Python function call?
...object.
This tool adds flexibility to existing functions or classes whose
output is hardwired to stdout.
For example, the output of help() normally is sent to sys.stdout. You
can capture that output in a string by redirecting the output to an
io.StringIO object:
f = io.StringIO() ...
Generating random numbers in Objective-C
...te the S-Boxes via
arc4random_addrandom().
There is no need to call arc4random_stir() before using arc4random(), since arc4random() automatically
initializes itself.
EXAMPLES
The following produces a drop-in replacement for the traditional rand() and random() functions using
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How to hide output of subprocess in Python 2.7
...
Redirect the output to DEVNULL:
import os
import subprocess
FNULL = open(os.devnull, 'w')
retcode = subprocess.call(['echo', 'foo'], stdout=FNULL, stderr=subprocess.STDOUT)
It is effectively the same as running this shell command:
retcode = os.system("echo 'fo...
Can't find the 'libpq-fe.h header when trying to install pg gem
...on Rails 3.1 pre version. I like to use PostgreSQL, but the problem is installing the pg gem. It gives me the following error:
...
Is MonoTouch now banned on the iPhone? [closed]
... C# then it would be violating the license:
...Applications must be originally written in Objective-C, C, C++, or JavaScript as executed by the iPhone OS WebKit engine...
They even hammer it in a little further:
Applications that link to Documented APIs through an intermediary translation or comp...
Bash command to sum a column of numbers [duplicate]
...mn of numbers. I just want a quick one liner that will do something essentially like this:
10 Answers
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Importing files from different folder
...ere from a search engine, this is not the answer you are looking for. Typically you would structure your files into packages (see other answers) instead of modifying the search path.
By default, you can't. When importing a file, Python only searches the directory that the entry-point script is runn...
pip broke. how to fix DistributionNotFound error?
...
Works great on Mac OS X 10.9 as well. Thanks!
– Anton Babenko
Oct 23 '13 at 16:56
2
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How do I get the directory that a program is running from?
... When I see code that looks at /proc part of me dies a little. All the world is not Linux, and even on that one platform /proc should be considered subject to change from version to version, arch to arch, etc.
– asveikau
Jan 28 '10 at 0:29
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