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IN vs OR in the SQL WHERE Clause
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I assume you want to know the performance difference between the following:
WHERE foo IN ('a', 'b', 'c')
WHERE foo = 'a' OR foo = 'b' OR foo = 'c'
According to the manual for MySQL if the values are constant IN sorts the list and then uses a binary search. I would imagine that OR evaluates t...
Why doesn't Objective-C support private methods?
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Private methods could not bypass the message dispatch. Consider the following scenario:
A class AllPublic has a public instance method doSomething
Another class HasPrivate has a private instance method also called doSomething
You create an array containing any number of instances of both AllPubl...
How do I specify the platform for MSBuild?
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Some projects use Win32 instead of x86 for instance, CMake generated ones do (libssh2 uses CMake).
– Jeroen Wiert Pluimers
Sep 13 '16 at 19:07
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How can you find the height of text on an HTML canvas?
...example of this working, I used this technique in the Carota editor.
Following on from ellisbben's answer, here is an enhanced version to get the ascent and descent from the baseline, i.e. same as tmAscent and tmDescent returned by Win32's GetTextMetric API. This is needed if you want to do a word-...
Need for predictable random generator
...o this time, again, they have a 1 in 5 chance. If they fail, next time the winning interval is 4 and 5; a 2 in 5 chance of success. With these choices, after 8 failures, they are certain to succeed.
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Why is the use of tuples in C++ not more common?
... mind). But while tuple is handy, it's not such an overwhelming and clear win that people bother with it.
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Wait until file is unlocked in .NET
...t, and the wait time between retries.
NOTE: Unfortunately, the underlying Win32 error (ERROR_SHARING_VIOLATION) is not exposed with .NET, so I have added a small hack function (IsSharingViolation) based on reflection mechanisms to check this.
/// <summary>
/// Wraps sharing violation...
Why does Clojure have “keywords” in addition to “symbols”?
... Is that it? Typing : rather than ' doesn't seem like a big win, especially since : is an extra keypress on most keyboards.
– Laurence Gonsalves
Oct 6 '09 at 19:29
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How can I programmatically generate keypress events in C#?
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The question is tagged WPF but the answers so far are specific WinForms and Win32.
To do this in WPF, simply construct a KeyEventArgs and call RaiseEvent on the target. For example, to send an Insert key KeyDown event to the currently focused element:
var key = Key.Insert; ...
Why do you not use C for your web apps?
...grams. That means you pay more.
Also, C doesn't have the benefit of drawing from an enormous single standard library of functionality as .NET (and the other major web-centric platforms) has. So you may have to either buy components, or perform interop, or roll your own functionality which comes...