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What's the $unwind operator in MongoDB?
...ad" }
],
other : { foo : 5 }
}
Notice how tags is actually an array of 3 items, in this case being "fun", "good" and "fun".
What $unwind does is allow you to peel off a document for each element and returns that resulting document.
To think of this in a classical approach, it would be the equiv...
Determine what attributes were changed in Rails after_save callback?
...nd
end
Or if you prefer, saved_change_to_attribute?(:published).
Rails 3–5.1
Warning
This approach works through Rails 5.1 (but is deprecated in 5.1 and has breaking changes in 5.2). You can read about the change in this pull request.
In your after_update filter on the model you can...
What do the numbers in a version typically represent (i.e. v1.9.0.1)?
... like 2.0.4.2709
You won't find a lot of apps going down to four levels, 3 is usually sufficient.
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How do I set default values for functions parameters in Matlab?
...gainst the number of arguments. Something like:
function f(arg1, arg2, arg3)
if nargin < 3
arg3 = 'some default'
end
end
There are a few fancier things you can do with isempty, etc., and you might want to look at Matlab central for some packages that bundle these sorts of things.
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Storing WPF Image Resources
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answered Mar 3 '09 at 16:02
Drew NoakesDrew Noakes
252k136136 gold badges593593 silver badges689689 bronze badges
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MySQL skip first 10 results
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edited May 23 '17 at 10:31
Community♦
111 silver badge
answered May 13 '10 at 13:17
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Dispelling the UIImage imageNamed: FUD
...is that the +imageNamed: cache should respect memory warnings on iPhone OS 3.0. Test it when you get a chance and report bugs if you find that this is not the case.
So, there you have it. imageNamed: will not smash your windows or murder your children. It's pretty simple but it is an optimisation t...
PHP foreach change original array values
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edited Oct 9 '17 at 13:30
answered Feb 22 '13 at 12:51
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What does jQuery.fn mean?
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853
In jQuery, the fn property is just an alias to the prototype property.
The jQuery identifier (o...
How to create a template function within a class? (C++)
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3
And also that you cannot specialize them. :-(
– Frank Krueger
Jun 9 '09 at 20:03
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