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mongodb count num of distinct values per field/key
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MongoDB has a distinct command which returns an array of distinct values for a field; you can check the length of the array for a count.
There is a shell db.collection.distinct() helper as well:
> db.countries.distinct('country');
[ "Spain", "Engl...
Rails: around_* callbacks
...api.rubyonrails.org/classes/ActiveRecord/Callbacks.html , but don't understand when the around_* callbacks are triggered in relation to before_* and after_* .
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CALayers didn't get resized on its UIView's bounds change. Why?
...you sure? it sounds like you are describing frame. bounds should, theoretically, always have 0,0 as its origin.
– griotspeak
Feb 11 '12 at 2:32
3
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Dynamically load a JavaScript file
How can you reliably and dynamically load a JavaScript file? This will can be used to implement a module or component that when 'initialized' the component will dynamically load all needed JavaScript library scripts on demand.
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How to write a JSON file in C#?
...ializeObject(_data.ToArray());
//write string to file
System.IO.File.WriteAllText(@"D:\path.txt", json);
Or the slightly more efficient version of the above code (doesn't use a string as a buffer):
//open file stream
using (StreamWriter file = File.CreateText(@"D:\path.txt"))
{
JsonSerializ...
How do I trim leading/trailing whitespace in a standard way?
... C? I'd roll my own, but I would think this is a common problem with an equally common solution.
38 Answers
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How can building a heap be O(n) time complexity?
...itten this to describe how a max heap works. This is the type of heap typically used for heap sort or for a priority queue where higher values indicate higher priority. A min heap is also useful; for example, when retrieving items with integer keys in ascending order or strings in alphabetical order...
How do I use spaces in the Command Prompt?
How can I use spaces in the Windows Command Line?
11 Answers
11
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UILabel text margin [duplicate]
...ilIndent = -10.0f;
NSAttributedString *attrText = [[NSAttributedString alloc] initWithString:title attributes:@{ NSParagraphStyleAttributeName : style}];
UILabel * label = [[UILabel alloc] initWithFrame:someFrame];
label.numberOfLines = 0;
label.attributedText = attrText;
Here is the above e...
Is it true that one should not use NSLog() on production code?
...with better functionality. Here's the one I use, it includes the file name and line number to make it easier to track down log statements.
#define DEBUG_MODE
#ifdef DEBUG_MODE
#define DebugLog( s, ... ) NSLog( @"<%p %@:(%d)> %@", self, [[NSString stringWithUTF8String:__FILE__] lastPathCo...