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How to 'bulk update' with Django?
...ings like incrementing rows:
from django.db.models import F
Entry.objects.all().update(n_pingbacks=F('n_pingbacks') + 1)
See the documentation.
However, note that:
This won't use ModelClass.save method (so if you have some logic inside it won't be triggered).
No django signals will be emitte...
In Django, how does one filter a QuerySet with dynamic field lookups?
...a custom ModelField/FormField/WidgetField that implemented the behavior to allow the user to, on the GUI side, basically "build" a query, never seeing the actual text, but using an interface to do so. Sounds like a neat project...
– T. Stone
Sep 23 '09 at 20:2...
How to include JavaScript file or library in Chrome console?
... aware of the fact that even getElementById() doesn't work consistently on all browsers - see this answer for details.)
UPDATE:
It's been years since I wrote this answer and I think it's worth pointing out here that today you can use:
SystemJS
ModuleLoader
jspm.io
to dynamically load scripts...
Python: changing value in a tuple
...'m new to python so this question might be a little basic. I have a tuple called values which contains the following:
17 ...
How do you split and unsplit a window/view in Eclipse IDE?
...tcut for splitting is:
Azerty keyboard:
Ctrl + _ for split horizontally, and
Ctrl + { for split vertically.
Qwerty US keyboard:
Ctrl + Shift + - (accessing _) for split horizontally, and
Ctrl + Shift + [ (accessing {) for split vertically.
MacOS - Qwerty US keyboard:
...
How to read a large file line by line?
...e line from the file.
echo $file->fgets();
}
// Unset the file to call __destruct(), closing the file handle.
$file = null;
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Chain-calling parent initialisers in python [duplicate]
... B inheriting from A, class C inheriting from B. What is a generic way to call a parent class initialiser in an initialiser? If this still sounds too vague, here's some code.
...
How to execute a raw update sql with dynamic binding in rails
...
It doesn't look like the Rails API exposes methods to do this generically. You could try accessing the underlying connection and using it's methods, e.g. for MySQL:
st = ActiveRecord::Base.connection.raw_connection.prepare("update table set f1=? where f2=? and f3=?")
st.execute(f1, f2, f3)
st...
jQuery selector regular expressions
...
James Padolsey created a wonderful filter that allows regex to be used for selection.
Say you have the following div:
<div class="asdf">
Padolsey's :regex filter can select it like so:
$("div:regex(class, .*sd.*)")
Also, check the official documentation on se...
Wait for a void async method
...
await Task.Run(() => An_async_void_method_I_can_not_modify_now())
– themefield
Mar 12 '19 at 21:46
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