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Create empty queryset by default in django form fields
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You can have an empty queryset by doing this:
MyModel.objects.none()
Although i don't know how are you going to use that form, you can put that as your field's queryset in order to get what you need...
You can find more information here
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What is object slicing?
...u assign an object of a derived class to an instance of a base class, thereby losing part of the information - some of it is "sliced" away.
For example,
class A {
int foo;
};
class B : public A {
int bar;
};
So an object of type B has two data members, foo and bar.
Then if you were to w...
Is there a way to make git pull automatically update submodules?
...recurse to true to enable the desired behaviour.
You can do this globally by running:
git config --global submodule.recurse true
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Sort array by firstname (alphabetically) in Javascript
I got an array (see below for one object in the array) that I need to sort by firstname using JavaScript.
How can I do it?
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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
... rows of X[Y] and Y[X] usually differ, whereas the number of rows returned by merge(X,Y) and merge(Y,X) is the same.
BUT that misses the main point. Most tasks require something to be done on the
data after a join or merge. Why merge all the columns of data, only to
use a small subset of th...
What is the difference between a strongly typed language and a statically typed language?
...tatically typed language has a type system that is checked at compile time by the implementation (a compiler or interpreter). The type check rejects some programs, and programs that pass the check usually come with some guarantees; for example, the compiler guarantees not to use integer arithmetic ...
How to have a default option in Angular.js select box
... I had a problem with this working, it was that I was using 'track by', removing it fixed the problem, just in case that helps someone down the line :D
– DrCord
Apr 15 '14 at 23:21
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undefined reference to `WinMain@16'
... 00000003 (Windows CUI)
C:\test> _
This means that the linker by default produced a console subsystem executable. The subsystem value in the file header tells Windows what services the program requires. In this case, with console system, that the program requires a console window.
This...
HTTP vs HTTPS performance
...rience, servers that are heavy on dynamic content tend to be impacted less by HTTPS because the time spent encrypting (SSL-overhead) is insignificant compared to content generation time.
Servers that are heavy on serving a fairly small set of static pages that can easily be cached in memory suffer ...
How to match, but not capture, part of a regex?
...ut this regular expression matches only apple or banana if it’s preceded by 123- and followed by -456, or it matches the empty string if it’s preceded by 123- and followed by 456.
|Lookaround | Name | What it Does |
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