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Difference between EXISTS and IN in SQL?
What is the difference between the EXISTS and IN clause in SQL?
21 Answers
21
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Swift variable decorations with “?” (question mark) and “!” (exclamation mark)
I understand that in Swift all variables must be set with a value, and that by using optionals we can set a variable to be set to nil initially.
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Is there an easy way to return a string repeated X number of times?
...t a certain number of indentations before a string based on an items depth and I'm wondering if there is a way to return a string repeated X times. Example:
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Is it possible to change a UIButtons background color?
...s until a web service responds. Must I change to highlight colour on press and have a timer change to disabled colour while waiting for the ws to respond? If I am missing the point can someone please explain. Thanks Polly.
– Polly
Aug 11 '12 at 11:05
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Calling virtual functions inside constructors
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Calling virtual functions from a constructor or destructor is dangerous and should be avoided whenever possible. All C++ implementations should call the version of the function defined at the level of the hierarchy in the current constructor and no further.
The C++ FAQ Lite covers this in sectio...
Auto expand a textarea using jQuery
How can I make a textarea automatically expand using jQuery?
31 Answers
31
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Convert string to number and add one
I want to turn the value I get from the id into a number and add one to it then pass the new value into the dosomething() function to use. When I tried this and the value is one I get back 11 not 2.
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How to implement WiX installer upgrade?
...omatic upgrades. It prevents downgrades, giving a localised error message, and also prevents upgrading an already existing identical version (i.e. only lower versions are upgraded):
<MajorUpgrade
AllowDowngrades="no" DowngradeErrorMessage="!(loc.NewerVersionInstalled)"
AllowSameVersionUp...
Getting the IP address of the current machine using Java
... the destination for Send/Recv, discards all packets from other addresses, and - which is what we use - transfers the socket into "connected" state, settings its appropriate fields. This includes checking the existence of the route to the destination according to the system's routing table and setti...
How to find the statistical mode?
In R, mean() and median() are standard functions which do what you'd expect. mode() tells you the internal storage mode of the object, not the value that occurs the most in its argument. But is there is a standard library function that implements the statistical mode for a vector (or list)?
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