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Difference between left join and right join in SQL Server [duplicate]
... Table1 right join Table2) to see a difference. This query should give you more rows, since Table2 contains a row with an id which is not present in Table1.
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With arrays, why is it the case that a[5] == 5[a]?
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I wonder if it isn't more like *((5 * sizeof(a)) + a). Great explaination though.
– John MacIntyre
Dec 19 '08 at 17:06
95
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Why do we need virtual functions in C++?
...rats. Should you overload func() so it takes a Cat*? If you have to derive more animals from Animal they would all need their own func().
The solution is to make eat() from the Animal class a virtual function:
class Animal
{
public:
virtual void eat() { std::cout << "I'm eating g...
Grouping functions (tapply, by, aggregate) and the *apply family
...b c
1 3 91
sapply(x, FUN = sum)
a b c
1 6 5005
In more advanced uses of sapply it will attempt to coerce the
result to a multi-dimensional array, if appropriate. For example, if our function returns vectors of the same length, sapply will use them as columns of a matrix:
sa...
How to check visibility of software keyboard in Android?
...otView.getHeight();
if (heightDiff > dpToPx(this, 200)) { // if more than 200 dp, it's probably a keyboard...
// ... do something here
}
}
});
Using a utility such as:
public static float dpToPx(Context context, float valueInDp) {
DisplayMetrics metrics = ...
What is wrong with using goto? [duplicate]
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I know this is an old post, but I thought I'd add one more use for goto. In SQR goto is commonly used as a 'continue' in a loop. Many database languages don't have continues in the language so they put a goto at the end of the loop and call it if they need to 'continue'.
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In Matplotlib, what does the argument mean in fig.add_subplot(111)?
...starts from 1 and increments row-first. See documentation of subplot() for more info.
– Christian Alis
Feb 2 '11 at 16:54
18
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Why does Twitter Bootstrap Use Pixels for Font Size?
...ully coherent enough. I'll try to blog about these changes as they come up more, but I'm unsure how close 3.0 is and what that will all entail yet.
I would suggest anyone with strong feelings about this go and +1 this thread.
[Update] V3 roadmap oulined in V2.3 release blogpost makes no mention of ...
Multi-line string with extra space (preserved indentation)
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Heredoc sounds more convenient for this purpose. It is used to send multiple commands to a command interpreter program like ex or cat
cat << EndOfMessage
This is line 1.
This is line 2.
Line 3.
EndOfMessage
The string after <&lt...