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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...QuerySet in the following ways:
Iteration. A QuerySet is iterable, and it executes its database query the first 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 ro...
Why is an array not assignable to Iterable?
...
Arrays can implement interfaces (Cloneable and java.io.Serializable). So why not Iterable? I guess Iterable forces adding an iterator method, and arrays don't implement methods. char[] doesn't even override toString. Anyway, arrays of references should be considered l...
C++ templates that accept only certain types
... class my_template<T*> {
...
};
// All other types are invalid, and will cause linker error messages.
[Minor EDIT 6/12/2013: Using a declared-but-not-defined template will result in linker, not compiler, error messages.]
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How does the Comma Operator work
...itializers for symbol tables. Thus, it makes the following syntax possible and meaningful:
keywords = "and", "or", "not", "xor";
Notice that due to operator precedence, the code is (intentionally!) identical to
(((keywords = "and"), "or"), "not"), "xor";
That is, the first operator called is k...
How do I make a batch file terminate upon encountering an error?
I have a batch file that's calling the same executable over and over with different parameters. How do I make it terminate immediately if one of the calls returns an error code of any level?
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quick random row selection in Postgres
... that contains couple of millions of rows. I have checked on the internet and I found the following
7 Answers
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XSD - how to allow elements in any order any number of times?
I am trying to create an XSD, and trying to write the definition with the following requirement:
6 Answers
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Managing large binary files with Git
I am looking for opinions of how to handle large binary files on which my source code (web application) is dependent. We are currently discussing several alternatives:
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Is there a Java equivalent or methodology for the typedef keyword in C++?
Coming from a C and C++ background, I found judicious use of typedef to be incredibly helpful. Do you know of a way to achieve similar functionality in Java, whether that be a Java mechanism, pattern, or some other effective way you have used?
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What is the difference between required and ng-required?
What is the difference between required and ng-required (form validation)?
3 Answers
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