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Delete everything in a MongoDB database
...way everything in a database—that is, to delete every single collection, and whatever else might be lying around, and start from scratch. Is there a single line of code that will let me do this? Bonus points for giving both a MongoDB console method and a MongoDB Ruby driver method.
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angular.service vs angular.factory
I have seen both angular.factory() and angular.service() used to declare services; however, I cannot find angular.service anywhere in official documentation.
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select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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Send attachments with PHP Mail()?
...cript from here: http://github.com/PHPMailer/PHPMailer
Extract the archive and copy the script's folder to a convenient place in your project.
Include the main script file -- require_once('path/to/file/class.phpmailer.php');
Now, sending emails with attachments goes from being insanely difficult t...
How to convert enum value to int?
... tax.getValue();
}
(I've changed the names to be a bit more conventional and readable, btw.)
This is assuming you want the value assigned in the constructor. If that's not what you want, you'll need to give us more information.
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How do I show/hide a UIBarButtonItem?
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Save your button in a strong outlet (let's call it myButton) and do this to add/remove it:
// Get the reference to the current toolbar buttons
NSMutableArray *toolbarButtons = [self.toolbarItems mutableCopy];
// This is how you remove the button from the toolbar and animate it
[toolb...
Python: fastest way to create a list of n lists
...None, n)]
It does not have to create a new int object in every iteration and is about 15 % faster on my machine.
Edit: Using NumPy, you can avoid the Python loop using
d = numpy.empty((n, 0)).tolist()
but this is actually 2.5 times slower than the list comprehension.
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When should I use std::thread::detach?
... also know join() waits until a thread completes. This is easy to understand, but what's the difference between calling detach() and not calling it?
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Explanation of the UML arrows
I have recently been studying UML and drawing simple diagrams with ordinary plain arrows between classes, but I know it's not enough. There are plenty of other arrows: generalization, realisation and etc. which have meaning to the diagram reader.
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How to remove leading and trailing white spaces from a given html string?
...ing HTML string. What would be sample code in JavaScript to remove leading and trailing white spaces from this string?
7 An...