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mongodb group values by multiple fields
...takes an "pipeline" expression as an argument instead of the "localFields" and "foreignFields" options. This then allows a "self-join" with another pipeline expression, in which we can apply $limit in order to return the "top-n" results.
db.books.aggregate([
{ "$group": {
"_id": "$addr",
"...
Maximum size of an Array in Javascript
Context: I'm building a little site that reads an rss feed, and updates/checks the feed in the background. I have one array to store data to display, and another which stores ID's of records that have been shown.
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Is it possible to change a UIButtons background color?
...s until a web service responds. Must I change to highlight colour on press and have a timer change to disabled colour while waiting for the ws to respond? If I am missing the point can someone please explain. Thanks Polly.
– Polly
Aug 11 '12 at 11:05
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How do BitTorrent magnet links work?
... I used a magnet link . Curious about how it works, I looked up the specs and didn't find any answers. The wiki says xt means "exact topic" and is followed by the format ( btih in this case) with a SHA1 hash. I saw base32 mentioned, knowing it's 5 bits per character and 32 characters, I found it...
Why isn't String.Empty a constant?
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which we can access from native.
I found this information from this handy article at CodeProject.
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How do you print in a Go test using the “testing” package?
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The structs testing.T and testing.B both have a .Log and .Logf method that sound to be what you are looking for. .Log and .Logf are similar to fmt.Print and fmt.Printf respectively.
See more details here: http://golang.org/pkg/testing/#pkg-index
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What's the “average” requests per second for a production web application?
...mory database...still need to test with live DB. DB may be our bottleneck and bring us back down unless we switch to nosql).
– Dean Hiller
Jun 6 at 0:28
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Declaring a custom android UI element using XML
How do I declare an Android UI element using XML?
6 Answers
6
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Get the real width and height of an image with JavaScript? (in Safari/Chrome)
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Webkit browsers set the height and width property after the image is loaded. Instead of using timeouts, I'd recommend using an image's onload event. Here's a quick example:
var img = $("img")[0]; // Get my img elem
var pic_real_width, pic_real_height;
$...
Visual Studio “Could not copy” … during build
...d success by doing the following:
Closing Visual Studio
Deleting the bin and obj folders, and
Reopening Visual Studio.
This "bug" has existed since Visual Studio 2003.
Finally, I have also found that I can often overcome this problem by simply renaming the executable file and then deleting it.
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