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Delete a key from a MongoDB document using Mongoose
....0 you can do:
User.update({_id: user._id}, {$unset: {field: 1 }}, callback);
And since version 2.4, if you have an instance of a model already you can do:
doc.field = undefined;
doc.save(callback);
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Android 'Unable to add window — token null is not for an application' exception
...- are you trying to create Dialog with an application context? Something like this:
new Dialog(getApplicationContext());
This is wrong. You need to use an Activity context.
You have to try like:
new Dialog(YourActivity.this);
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When to use “ON UPDATE CASCADE”
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It's true that if your primary key is just a identity value auto incremented, you would have no real use for ON UPDATE CASCADE.
However, let's say that your primary key is a 10 digit UPC bar code and because of expansion, you need to change it to a 13-dig...
Version number comparison in Python
I want to write a cmp -like function which compares two version numbers and returns -1 , 0 , or 1 based on their compared valuses.
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Date vs DateTime
I am working on a program that requires the date of an event to get returned.
12 Answers
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How to sort an array of associative arrays by value of a given key in PHP?
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You are right, the function you're looking for is array_multisort().
Here's an example taken straight from the manual and adapted to your case:
$price = array();
foreach ($inventory as $key => $row)
{
$price[$key] = $row['price'];
}
array_multisort($price,...
Default constructor with empty brackets
Is there any good reason that an empty set of round brackets (parentheses) isn't valid for calling the default constructor in C++?
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Provisioning Profiles menu item missing from Xcode 5
... I don't have a menu item for Library - Provisioning Profiles, and I don't know what could have happened. I restarted the computer, tried some things, but I really have no idea what I could do. How can I fix this problem?
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How do I convert an NSString value to NSData?
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ldiqual
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answered May 23 '09 at 11:34
flitzwaldflitzwald
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Should I put the Google Analytics JS in the or at the end of ?
... the end of the <head> section helps ensure the your metrics are tracked even when a user doesn't let the page finish loading.
They used to tell you to put it at the bottom of the page, before they added support for handling partial loading of pages.
Directly from Google:
One of the main...