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Django - limiting query results
...s are lazy. That means a query will hit the database only when you specifically ask for the result.
So until you print or actually use the result of a query you can filter further with no database access.
As you can see below your code only executes one sql query to fetch only the last 10 items.
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How do you properly use namespaces in C++?
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Namespaces are packages essentially. They can be used like this:
namespace MyNamespace
{
class MyClass
{
};
}
Then in code:
MyNamespace::MyClass* pClass = new MyNamespace::MyClass();
Or, if you want to always use a specific namespace, you can d...
Changing .gitconfig location on Windows
...r, to give it the effect you desire, you need to pass the --global flag to all git invocations (plus any local .git/config files are ignored).
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Codesign error: Certificate identity appearing twice
...same problem.
It has been fixed.
It came after I submitted an app and installed a few certificates to sign the app.
Quick Fix:
Open up KEYCHAIN ACCESS > click on MY CERTIFICATES> in there you will probably see
iPhone Developer: . You will probably see it TWICE!
Select the one with the earl...
How to complete a git clone for a big project on an unstable connection?
...pted clone. It may take
considerable time for a user on the
end of a small pipe to download the
data, and if the clone is interrupted
in the middle the user currently needs
to start over from the beginning and
try again. For some users this may
make it impossible to clone a large
rep...
'size_t' vs 'container::size_type'
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The standard containers define size_type as a typedef to Allocator::size_type (Allocator is a template parameter), which for std::allocator<T>::size_type is typically defined to be size_t (or a compatible type). So for the standard case, they are the same.
However, if you us...
jQuery’s .bind() vs. .on()
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Internally, .bind maps directly to .on in the current version of jQuery. (The same goes for .live.) So there is a tiny but practically insignificant performance hit if you use .bind instead.
However, .bind may be removed from futu...
Controlling a USB power supply (on/off) with Linux
Is it possible to turn on/off power supplies from USB manually with Linux?
10 Answers
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Disable VS' “downloading public symbols”
...ymbols option page
Tools → Options
Go To Debugging → Symbols
Uncheck all of the listed symbol file locations
Also you may want to disable "Enable .net framework source stepping" in Tools → Options → Debugging settings.
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Get table name by constraint name [duplicate]
... name of the table. If you don't have access to the DBA_CONSTRAINTS view, ALL_CONSTRAINTS or USER_CONSTRAINTS should work as well.
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