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What's the $unwind operator in MongoDB?
...hat it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what the use case that you ...
Why aren't variable-length arrays part of the C++ standard?
...agree that having to create a potential large array on the stack, which usually has only little space available, isn't good. The argument is, if you know the size beforehand, you can use a static array. And if you don't know the size beforehand, you will write unsafe code.
C99 VLAs could provide a...
Interface vs Base class
... and let's illustrate using C#:
Both a dog and a cat are animals, specifically, quadruped mammals (animals are waaay too general). Let us assume that you have an abstract class Mammal, for both of them:
public abstract class Mammal
This base class will probably have default methods such as:
Fe...
SQL Server Script to create a new user
...fluid than I make it seem above. For example, a Login account is automatically created (in most SQL Server installations) for the Windows Administrator account when the database is installed. In most situations, I just use that when I am administering a database (it has all privileges).
However...
Loop through files in a directory using PowerShell
How can I change the following code to look at all the .log files in the directory and not just the one file?
4 Answers
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When I catch an exception, how do I get the type, file, and line number?
...Error:
print(traceback.format_exc())
Output
Traceback (most recent call last):
File "/path/to/file.py", line 51, in <module>
print(4/0)
ZeroDivisionError: division by zero
Process finished with exit code 0
...
How do I calculate the normal vector of a line segment?
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
converting a .net Func to a .net Expression
Going from a lambda to an Expression is easy using a method call...
9 Answers
9
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C# : 'is' keyword and checking for Not
...
32
@Frank it works because is has higher precedence relative to ==. The only reason you can't use !x is f is that it has less precedence than ...
Adding external library into Qt Creator project
... this is like this:
LIBS += -L/path/to -lpsapi
This way it will work on all platforms supported by Qt. The idea is that you have to separate the directory from the library name (without the extension and without any 'lib' prefix). Of course, if you are including a Windows specific lib, this reall...