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Does MongoDB's $in clause guarantee order
...course will be the natural order or by the selected 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 ].
Appr...
Clone contents of a GitHub repository (without the folder itself)
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If the current directory is empty, you can do that with:
git clone git@github:me/name.git .
(Note the . at the end to specify the current directory.) Of course, this also creates the .git directory in your current folder,...
STAThread and multithreading
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Apartment threading is a COM concept; if you're not using COM, and none of the APIs you call use COM "under the covers", then you don't need to worry about apartments.
If you do need to be aware of apartments, then the details can get a little complicated; a pro...
How can I convert a comma-separated string to an array?
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While split will work fine if you are sure you have elements in array, if you're expecting data from a server / database you will run into trouble since ''.split(',') has a length === 1 IE: ''.split(',') === ['']
– oportocala
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cancelling a handler.postdelayed process
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If you can afford to cancel all callbacks and messages on the handler and don't want to have to keep references to the runnable the third point in the accepted answer to this question is another alternative that seems to work...
Can I serve multiple clients using just Flask app.run() as standalone?
...tly pass threaded=True to enable this behaviour.
For example, you can do
if __name__ == '__main__':
app.run(threaded=True)
to handle multiple clients using threads in a way compatible with old Flask versions, or
if __name__ == '__main__':
app.run(threaded=False, processes=3)
to tell W...
HTML5 Number Input - Always show 2 decimal places
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This does not work in Chrome 55.0.2883.75. If I create a form element, place the markup above inside, type '1200' into the input and hit tab away from the element, the text displayed is still '1200' and not '1200.00'.
– Rick Glos
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How to find out if an installed Eclipse is 32 or 64 bit version?
How can I find out if a specific Eclipse instance on my (Windows 7) PC is the 32-bit or 64-bit version?
5 Answers
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instanceof Vs getClass( )
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The reason that the performance of instanceof and getClass() == ... is different is that they are doing different things.
instanceof tests whether the object reference on the left-hand side (LHS) is an instance of the type on the right-hand side (RHS) or some subtype.
getClass() == ... tests wh...
Is the SQL WHERE clause short-circuit evaluated?
...icularly when operands or operators might
cause conditions to be raised or if the results of the expressions
can be determined without completely evaluating all parts of the
expression.
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