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Does MongoDB's $in clause guarantee order
...d index order as shown.
If you need to preserve this order, then you basically have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
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Ruby get object keys as array
...Hash:
http://ruby-doc.org/core-1.9.3/Hash.html#method-i-keys
You'll find all the different methods available for each class.
If you don't know what you're dealing with:
puts my_unknown_variable.class.to_s
This will output the class name.
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String concatenation vs. string substitution in Python
...catenation is (significantly) faster according to my machine. But stylistically, I'm willing to pay the price of substitution if performance is not critical. Well, and if I need formatting, there's no need to even ask the question... there's no option but to use interpolation/templating.
>>&g...
How exactly does the “Specific Version” property of an assembly reference work in Visual Studio?
...ble about how the property works. Even SO, it appears to me, does not have all the answers, so here is my attempt at self-answering the question:
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How to make MySQL handle UTF-8 properly
... My understanding is that utf8 within MySQL only refers to a small subset of full Unicode. You should use utf8mb4 instead to force full support. See mathiasbynens.be/notes/mysql-utf8mb4 "For a long time, I was using MySQL’s utf8 charset for databases, tables, and columns, assuming i...
Apply style to only first level of td tags
...in IE6. If you need to support that browser (which you probably do, alas), all you can do is select the inner element separately and un-set the style:
.MyClass td { border: solid 1px red; }
.MyClass td td { border: none; }
*Note that the first example references a tbody element not found in you...
How do I get a PHP class constructor to call its parent's parent's constructor?
I need to have a class constructor in PHP call its parent's parent's (grandparent?) constructor without calling the parent constructor.
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RESTful Alternatives to DELETE Request Body
While the HTTP 1.1 spec seems to allow message bodies on DELETE requests, it seems to indicate that servers should ignore it since there are no defined semantics for it.
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Getting SyntaxError for print with keyword argument end=' '
...print ("foo" % bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to print with a tuple as argument.
That's obviously bad syntax (literals don't take keyword arguments). In Python 3.x print is an actual function, so it takes keyword arguments, too.
The correct idiom in Python 2.x for ...
Parallel foreach with asynchronous lambda
I would like to handle a collection in parallel, but I'm having trouble implementing it and I'm therefore hoping for some help.
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