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Why does NULL = NULL evaluate to false in SQL server
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Think of the null as "unknown" in that case (or "does not exist"). In either of those cases, you can't say that they are equal, because you don't know the value of either of them. So, null=null evaluates to not true (false or null, depending on your system), because you don't know ...
What are the GCC default include directories?
...e default paths used by gcc/g++, as well as their priorities, you need to examine the output of the following commands:
For C:
gcc -xc -E -v -
For C++:
gcc -xc++ -E -v -
The credit goes to Qt Creator team.
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Aligning rotated xticklabels with their respective xticks
Check the x axis of the figure below. How can I move the labels a bit to the left so that they align with their respective ticks?
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Why is pow(a, d, n) so much faster than a**d % n?
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See the Wikipedia article on modular exponentiation. Basically, when you do a**d % n, you actually have to calculate a**d, which could be quite large. But there are ways of computing a**d % n without having to compute a**d itself, and that is what pow does. Th...
Using scanf() in C++ programs is faster than using cin?
...a simple case: a program to read a list of numbers from standard input and XOR all of the numbers.
iostream version:
#include <iostream>
int main(int argc, char **argv) {
int parity = 0;
int x;
while (std::cin >> x)
parity ^= x;
std::cout << parity << std::en...
Is there a “goto” statement in bash?
...ash Reference Manual for information about the control structures that do exist. In particular, note the mention of break and continue, which aren't as flexible as goto, but are more flexible in Bash than in some languages, and may help you achieve what you want. (Whatever it is that you want . . .)...
(grep) Regex to match non-ASCII characters?
On Linux, I have a directory with lots of files. Some of them have non-ASCII characters, but they are all valid UTF-8 . One program has a bug that prevents it working with non-ASCII filenames, and I have to find out how many are affected. I was going to do this with find and then do a grep to p...
jQuery how to find an element based on a data-attribute value?
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this answer on a similar post has an example of the filter function
– drzaus
Jul 26 '12 at 16:08
78
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Will using 'var' affect performance?
Earlier I asked a question about why I see so many examples use the varkeyword and got the answer that while it is only necessary for anonymous types, that it is used nonetheless to make writing code 'quicker'/easier and 'just because'.
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Close Window from ViewModel
... can pass the window to your ViewModel using the CommandParameter. See my Example below.
I've implemented an CloseWindow Method which takes a Windows as parameter and closes it. The window is passed to the ViewModel via CommandParameter. Note that you need to define an x:Name for the window which s...