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When should I use mmap for file access?
...he buffers are often properly aligned and do not trap when dereferencing a casted pointer.
You also have to be careful that you do not access outside of the map. It can easily happen if you use string functions on your map, and your file does not contain a \0 at the end. It will work most of the ti...
What is the significance of 1/1/1753 in SQL Server?
...ith the greater range of datetime2
SELECT CONVERT(VARCHAR, DATEADD(DAY,-5,CAST('1752-09-13' AS DATETIME2)),100)
Returns
Sep 8 1752 12:00AM
One final point with the datetime2 data type is that it uses the proleptic Gregorian calendar projected backwards to well before it was actually invented ...
Meaning of acronym SSO in the context of std::string
...h_resolution_clock::now();
const auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(t2 - t1).count();
std::cerr << list[0].length() << ',' << duration << '\n';
}
void addRandomString(std::vector<std::string>& list, const int length)...
Can a class member function template be virtual?
...ing>* p = &a;
p->func1("A<string> a");
p = dynamic_cast<A<string>*>(&c);
p->func1("B<string> c");
B<int>* q = &b;
q->func1(3);
}
and the output is:
A:A<string> a
A<--B:B<string> c
A<--B:3
And later I add...
When and why would you seal a class?
... think this post has some good point, the specific case was when trying to cast a non-sealed class to any random interface, compiler doesn't throw error; but when sealed is used the compiler throws error that it can't convert. Sealed class brings additional code access security.
https://www.codeproj...
What is more efficient? Using pow to square or just multiply it with itself?
...();
}
double elapsed() const {
return std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::high_resolution_clock::now() - from).count() * 1.0e-6;
}
private:
std::chrono::high_resolution_clock::time_point from;
};
int main (int argc, char* argv[])
{
do...
Best way to compare two complex objects
....Equals method (whose execution would be marginally slower due to the type cast).
When you override Object.Equals, you’re also expected to override Object.GetHashCode; I didn’t do so below for the sake of conciseness.
public class Person : IEquatable<Person>
{
public int Age { get; s...
What exactly do “u” and “r” string flags do, and what are raw string literals?
...by calling unicode('text')
So u is just a short way to call a function to cast str to unicode. That's it!
Now the r part, you put it in front of the text to tell the computer that the text is raw text, backslash should not be an escaping character. r'\n' will not create a new line character. It's ...
Are there any disadvantages to always using nvarchar(MAX)?
...ost everything, from index to delete, update and inserts. "
http://sqlblogcasts.com/blogs/simons/archive/2006/02/28/Why-use-anything-but-varchar_2800_max_2900_.aspx
Integration implications - hard for other systems to know how to integrate with your database
Unpredictable growth of data
Possible s...
C++11 rvalues and move semantics confusion (return statement)
...emporary created on the return line. move doesn't create a temporary. It casts an lvalue to an xvalue, making no copies, creating nothing, destroying nothing. That example is the exact same situation as if you returned by lvalue-reference and removed the move from the return line: Either way you...