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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...rst time you iterate over it. For example, this will print the headline of all entries in the database:
for e in Entry.objects.all():
print e.headline
So your ten million rows are retrieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait ...
New Array from Index Range Swift
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Pedantic point, but this isn't really casting the Slice to an Array, but rather creating a new array from a slice. A cast would use the as operator: numbers as Array which would result in an error.
– j b
Jun 10 '14 at 9...
What characters are allowed in DOM IDs? [duplicate]
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Actually there is a difference between HTML and XHTML.
As XHTML is XML the rules for XML IDs apply:
Values of type ID MUST match the Name production.
NameStartChar ::= ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6] |
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Where is shared_ptr?
...rking). Simply stating std , tr1 and <memory> is not helping at all! I have downloaded boosts and all but still it doesn't show up! Can someone help me by telling exactly where to find it?
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How do I obtain crash-data from my Android application?
...n? At least when working on my own device being retrieved by cable, but ideally from any instance of my application running on the wild so that I can improve it and make it more solid.
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How can I programmatically check whether a keyboard is present in iOS app?
... responder. I have a view controller with multiple child view controllers, all of which contain UITextFields. Using this method, i cannot tell from my parent view controller whether the keyboard is shown. The only reliable way is to use the notification method explained in the other answers
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How to find if a native DLL file is compiled as x64 or x86?
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You can use DUMPBIN too. Use the /headers or /all flag and its the first file header listed.
dumpbin /headers cv210.dll
64-bit
Microsoft (R) COFF/PE Dumper Version 10.00.30319.01
Copyright (C) Microsoft Corporation. All rights reserved.
Dump of file cv210.dll
PE ...
How to avoid 'cannot read property of undefined' errors?
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Catching all exceptions without re-throwing is bad, and generally using exceptions as part of the expected flow of execution is also not great -- even though in this case it's pretty well contained.
– hugo
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Extending an Object in Javascript
... I have one question: how is the Person() constructor being called when you do new Robot()? It seems to me that you should call that base class constructor instead of doing this.name = name; in the Robot() constructor...
– Alexis Wilke
Apr 7 '14 a...
Referencing system.management.automation.dll in Visual Studio
...g it updated, releasing new packages, etc.
– Ben Randall
Feb 5 '16 at 19:24
last updated 29/03/2013 " The owner has un...