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Favourite performance tuning tricks [closed]
...Nice Joins
By default the optimiser will only consider the tables 4 at a time.
This means that in joins with more than 4 tables, it has a good chance of choosing a non-optimal query plan
Break up the Join
Can you break up the join?
Pre-select foreign keys into a temporary table
Do half the ...
Get current time as formatted string in Go?
What's the best way to get the current timestamp in Go and convert to string? I need both date and time in eg. YYYYMMDDhhmmss format.
...
NOT IN vs NOT EXISTS
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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.
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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();
...
Remove whitespaces inside a string in javascript
...his regExp is faster because you can remove one or more spaces at the same time.
If you change the replacement empty string to '$', the difference becomes much clearer:
var string= ' Q W E R TY ';
console.log(string.replace(/\s/g, '$')); // $$Q$$W$E$$$R$TY$
console.log(string.replace(/\s+/g,...
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 ...
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...
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...
How to best position Swing GUIs?
...owing system or at the current location (returned by getLocation) the next time the Window is made visible. This behavior resembles a native window shown without programmatically setting its location. Most windowing systems cascade windows if their locations are not explicitly set. The actual locati...
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
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