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Difference between clustered and nonclustered index [duplicate]
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You really need to keep two issues apart:
1) the primary key is a logical construct - one of the candidate keys that uniquely and reliably identifies every row in your table. This can be anything, really - an INT, a GUID, a string...
What do the parentheses around a function name mean?
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In the absence of any preprocessor stuff going on, foo's signature is equivalent to
int foo (int *bar)
The only context in which I've seen people putting seemingly unnecessary parentheses around function names is when there are both a function and a function-like macro wit...
'any' vs 'Object'
...ate an error telling you exactly that. If you use any instead you are basically telling the transpiler that anything goes, you are providing no information about what is stored in a - it can be anything! And therefore the transpiler will allow you to do whatever you want with something defined as an...
How do I implement IEnumerable
...>'s GetEnumerator in the explicit implementation of IEnumerable:
class FooCollection : IEnumerable<Foo>, IEnumerable
{
SomeCollection<Foo> foos;
// Explicit for IEnumerable because weakly typed collections are Bad
System.Collections.IEnumerator IEnumerable.GetEnumerator(...
The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
... assignment.
Consider the case of data extraction on the following list:
foo <- list( str='R', vec=c(1,2,3), bool=TRUE )
Say we would like to extract the value stored by bool from foo and use it inside an if() statement. This will illustrate the differences between the return values of [] and...
Can I “multiply” a string (in C#)?
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I don't think it's elegant at all. In python the code to do this is: snip * multiplier (It's not horrible.. but neither is it beautiful).
– demented hedgehog
Jun 2 '15 at 2:56
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SetUnhandledExceptionFilter and the C/C++ Runtime Library - C/C++ - 清...
...unctionality by the means of the SetUnhandledExceptionFilter function.
Usually, the SetUndhandledExceptionFilter function is used in conjunction with the crash reporting activity. Having the ability of pinpointing the line of code which caused a crash is invaluable in post mortem debugging.
Post m...
Difference between PCDATA and CDATA in DTD
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PCDATA - Parsed Character Data
XML parsers normally parse all the text in an XML document.
CDATA - (Unparsed) Character Data
The term CDATA is used about text data that should not be parsed by the XML parser.
Characters like "<" and "&" are illegal in XML elemen...
What is the difference between `let` and `var` in swift?
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C and C++ allows Unicode identifiers as well, via UCNs. If the compiler supports any Unicode source encoding then you can just use the Unicode characters directly. For example auto ???????? = "dogcow"; works in C++ for clang.
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Java generics T vs Object
...ds of Object.
But with context - if you have a generic class:
MyClass<Foo> my = new MyClass<Foo>();
Foo foo = new Foo();
Then:
Foo newFoo = my.doSomething(foo);
Same code with object
Foo newFoo = (Foo) my.doSomething(foo);
Two advantages:
no need of casting (the compiler hide...