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MySQL: selecting rows where a column is null
...= NULL is always false).
See Rule 3 https://en.wikipedia.org/wiki/Codd%27s_12_rules
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How can I call a custom Django manage.py command directly from a test driver?
...cannot decouple logic form command you can call it from any code using call_command method like this:
from django.core.management import call_command
call_command('my_command', 'foo', bar='baz')
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how perform grep operation on all files in a directory
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Highly active question. Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity.
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How do I execute a command and get the output of the command within C++ using POSIX?
...std::array<char, 128> buffer;
std::string result;
std::unique_ptr<FILE, decltype(&pclose)> pipe(popen(cmd, "r"), pclose);
if (!pipe) {
throw std::runtime_error("popen() failed!");
}
while (fgets(buffer.data(), buffer.size(), pipe.get()) != nullptr) {
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What's the best/easiest GUI Library for Ruby? [closed]
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AFAIK shoes.heroku.com is the new post-_why home for all things shoes.
– Pete Hodgson
Feb 4 '10 at 23:45
1
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Kill detached screen session [closed]
...sion.
~$ screen -list
There are screens on:
20751.Melvin_Peter_V42 (Detached)
Note: 20751.Melvin_Peter_V42 is your session id.
Get attached to the detached screen session
screen -r 20751.Melvin_Peter_V42
Once connected to the session press Ctrl + A then type :quit
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What is the relationship between UIView's setNeedsLayout, layoutIfNeeded and layoutSubviews?
...tion might look something like this:
-(void)layoutIfNeeded {
if (self._needsLayout) {
UIView *sv = self.superview;
if (sv._needsLayout) {
[sv layoutIfNeeded];
} else {
[self layoutSubviews];
}
}
}
You would call layoutIfNeeded on a v...
How to disable / enable dialog negative positive buttons?
...ertDialog.Builder(MainActivity.this);
builder.setIcon(android.R.drawable.ic_dialog_info);
builder.setTitle("Alert dialog title");
builder.setMessage("This is the example code snippet to disable button if edittext attached to dialog is empty.");
builder.setPositiveButton("PositiveButton",
new...
How to get the response of XMLHttpRequest?
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How to best position Swing GUIs?
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