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The JPA hashCode() / equals() dilemma
... It is a great article. However, for people who see the link for the first time, I would suggest that it might be an overkill for most applications. The other 3 options listed on this page should more or less solve the issue in multiple ways.
– HopeKing
Jul 1 '...
NOT IN vs NOT EXISTS
...
execution planner time may be same but execution results can differ so there is a difference. NOT IN will produce unexpected results if you have NULL in your dataset (see buckley's answer). Best to use NOT EXISTS as a default.
...
Casting vs using the 'as' keyword in the CLR
... is followed by a cast.
I don't think any of the answers so far (at the time of starting this answer!) have really explained where it's worth using which.
Don't do this:
// Bad code - checks type twice for no reason
if (randomObject is TargetType)
{
TargetType foo = (TargetType) randomObje...
Random date in C#
...
private Random gen = new Random();
DateTime RandomDay()
{
DateTime start = new DateTime(1995, 1, 1);
int range = (DateTime.Today - start).Days;
return start.AddDays(gen.Next(range));
}
For better performance if this will be called repeated...
Write a program that will surely go into deadlock [closed]
...it();
} catch (InterruptedException e) {
throw new RuntimeException();
}
synchronized (obj2) {
System.out.println("Thread finished");
}
}
}
public static void main(String[] args) {
final Object obj1 = new Object();
...
CALayers didn't get resized on its UIView's bounds change. Why?
...-like", or "link-to-superlayer"-like solution? Oh, god, another day out of time-frame. CGLayers got resized, but was too laggy, CALayers are fast enough, but did not get resized. So many surprise. Thanks for the reply, anyway.
– Geri Borbás
Mar 24 '10 at 11:46...
printf with std::string?
..."Press ENTER to quit program!";
cout << "Come up and C++ me some time." << endl;
printf("Follow this command: %s", myString.c_str()); //note the use of c_str
cin.get();
return 0;
}
If you want a function that is like printf, but type safe, look into variadic templates ...
How do I upgrade PHP in Mac OS X?
... make it work are on that page (I was stupid enough to miss that the first time).
– Coded Monkey
Apr 10 '14 at 18:52
...
How to convert current date into string in java?
... Used a combination of this and the answer right below for the timestring. C:
– php_coder_3809625
Jul 13 '16 at 13:54
...
How to append rows to an R data frame
...icrobenchmark" package will give us more comprehensive insight than system.time:
library(microbenchmark)
microbenchmark(f1(1000), f3(1000), f4(1000), times = 5)
# Unit: milliseconds
# expr min lq median uq max neval
# f1(1000) 1024.539618 1029.693877 1045...