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How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...
fatal error: malformed or corrupted AST file - Xcode
...olved the issue for me. In Xcode, go to Window->Organizer->Projects, select your project, and press the "Delete..." button next to "Derived data".
If this doesn't work, you can try to do a Product->Clean (Cmd+Shift+k).
...
Segue to another storyboard?
...;
// Load the initial view controller from the storyboard.
// Set this by selecting 'Is Initial View Controller' on the appropriate view controller in the storyboard.
UIViewController *theInitialViewController = [secondStoryBoard instantiateInitialViewController];
//
// **OR**
//
// Load the view...
Set value of hidden field in a form using jQuery's “.val()” doesn't work
...ontribute to any problems you're having, and specifying a more complicated selector just slows things down and doesn't look as neat.
Example at http://jsbin.com/elovo/edit, using your example code at http://jsbin.com/elovo/2/edit
...
How can I process each letter of text using Javascript?
... matters, use this:
for (var i = 0; i < str.length; i++) {
alert(str.charAt(i));
}
If the order of alerts doesn't matter, use this:
var i = str.length;
while (i--) {
alert(str.charAt(i));
}
var str = 'This is my string';
function matters() {
for (var i = 0; i < str.length; ...
What is the difference between string primitives and String objects in JavaScript?
...plains the much faster random access speed.
So what happens when you do s.charAt(i) for instance?
Since s is not an instance of String, JavaScript will auto-box s, which has typeof string to its wrapper type, String, with typeof object or more precisely s.valueOf(s).prototype.toString.call = [obje...
android:drawableLeft margin and/or padding
...r drawable resources.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_checked="true">
<inset android:drawable="@drawable/small_m" android:insetLeft="10dp" android:insetTop="10dp" /&g...
When to use .First and when to use .FirstOrDefault with LINQ?
... The only thing I'd add is that if the default value for the type you're selecting could be a valid value, for instance your result might be the int value 0, then handling the exception seems to be the best way to handle this.
– PeterBelm
Apr 19 '12 at 8:59
...
Reliable method to get machine's MAC address in C#
...aces()
where nic.OperationalStatus == OperationalStatus.Up
select nic.GetPhysicalAddress().ToString()
).FirstOrDefault();
Or:
String firstMacAddress = NetworkInterface
.GetAllNetworkInterfaces()
.Where( nic => nic.OperationalStatus == OperationalStatus.Up &&...
Parallel.ForEach vs Task.Run and Task.WhenAll
...e that your second example can be shortened to
await Task.WhenAll(strings.Select(s => Task.Run(() => DoSomething(s)));
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