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mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
Python executable not finding libpython shared library
I am installing Python 2.7 on CentOS 5. I built and installed Python as follows
9 Answers
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Git Bash is extremely slow on Windows 7 x64
...ve been using Git on both Windows and Ubuntu during the development of a small project, frequently flipping back and forth between the two. The issue is that Git Bash consistently becomes slow.
...
Keyboard Interrupts with python's multiprocessing Pool
...s to set up the worker processes to ignore SIGINT altogether, and confine all the cleanup code to the parent process. This fixes the problem for both idle and busy worker processes, and requires no error handling code in your child processes.
import signal
...
def init_worker():
signal.sign...
How to use base class's constructors and assignment operator in C++?
...
You can explicitly call constructors and assignment operators:
class Base {
//...
public:
Base(const Base&) { /*...*/ }
Base& operator=(const Base&) { /*...*/ }
};
class Derived : public Base
{
int additional_;
public:
...
Why is it impossible to override a getter-only property and add a setter? [closed]
Why is the following C# code not allowed:
16 Answers
16
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How to remove from a map while iterating it?
...= m.erase(it)" since C++11
}
else
{
++it;
}
}
Note that we really want an ordinary for loop here, since we are modifying the container itself. The range-based loop should be strictly reserved for situations where we only care about the elements. The syntax for the RBFL makes this clear...
Label Alignment in iOS 6 - UITextAlignment deprecated
...MAY change at some time in the future and cause unexpected results. That's all. No doomsday scenario in this case, but better practices should prevail.
– Brenden
Nov 2 '12 at 19:36
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MongoDB mongorestore failure: locale::facet::_S_create_c_locale name not valid
...
On my distro "locale-gen" was not installed and it turned out all I had to do is set the LC_ALL environment variable.
so the following command fixed it:
export LC_ALL="en_US.UTF-8"
hopefully it will help someone else...
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How do you validate a URL with a regular expression in Python?
...he result of parsing gives you a netloc or path you don't like, you could call that "invalid".
– S.Lott
Jun 29 '09 at 20:44
2
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