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Is there any performance gain in indexing a boolean field?
...QL can quickly determine the position to seek to in the middle of the data file without having to look at all the data.
I think it's also safe to say an index will not DECREASE performance in this case, so you have only to gain from it.
...
Multiple Inheritance in PHP
... is just a sample) where you want to have generic things like debug into a file, send SMS for critical problem and so on. All your classes are children of this class. Now suppose you want to create a class Exception that should have those functions (= child of Tracing). This class must be a child of...
how to override left:0 using CSS or Jquery?
... {
left: auto;
}
Make sure that the above comes after the original CSS file.
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How do I alter the position of a column in a PostgreSQL database table?
...g_dump -s databasename > databasename_schema.sql). Next edit the schema file to rearrange the columns as you would like, then recreate the database from the schema, and finally restore the data into the newly created database.
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How can I detect the touch event of an UIImageView?
...
To add a touch event to a UIImageView, use the following in your .m file:
UITapGestureRecognizer *newTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(myTapMethod)];
[myImageView setUserInteractionEnabled:YES];
[myImageView addGestureRecognizer:newTap];
-(void)myT...
How can I determine whether a Java class is abstract by reflection
I am interating through classes in a Jar file and wish to find those which are not abstract. I can solve this by instantiating the classes and trapping InstantiationException but that has a performance hit as some classes have heavy startup. I can't find anything obviously like isAbstract() in the C...
Do Swift-based applications work on OS X 10.9/iOS 7 and lower?
...n, just adding a button programmatically. My application contains only two files, AppDelegate.swift and ViewController.swift.
So if you are not using any new APIs added as part of the iOS 8 SDK or some Swift specific APIs (corresponding API is not available for Objective-C) your application will se...
Open terminal here in Mac OS finder [closed]
...y, you can avoid using the mouse.
I've added the following to my .bash_profile so I can type cdff in Terminal at any time.
function ff { osascript -e 'tell application "Finder"'\
-e "if (${1-1} <= (count Finder windows)) then"\
-e "get POSIX path of (target of window ${1-1} as alias)"\
-e ...
Renew Provisioning Profile
Just got a notice that the provisioning profile for one of my apps is about to expire. Is there some way I can renew the existing one or must I recreate a new one?
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Android: What is android.R.id.content used for?
... in this rootview.
As of version 19, android.R.id.content is defined in a file: auto_complete_list.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/content"
android:orientation="vertical"
android:layout_width="match_parent"
androi...