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How do I clone a Django model instance object and save it to the database?
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Just change the primary key of your object and run save().
obj = Foo.objects.get(pk=<some_existing_pk>)
obj.pk = None
obj.save()
If you want auto-generated key, set the new key to None.
More on UPDATE/INSERT here.
Official docs on copying model instances: h...
Generate unique random numbers between 1 and 100
How can I generate some unique random numbers between 1 and 100 using JavaScript?
29 Answers
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Render a string in HTML and preserve spaces and linebreaks
...As part of that I have a description (retrieved from a db) that has spaces and new lines. When it is rendered the new lines and spaces are ignored by the html. I would like to encode those spaces and new lines so that they aren't ignored.
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Why should I use version control? [closed]
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Have you ever:
Made a change to code, realised it was a mistake and wanted to revert back?
Lost code or had a backup that was too old?
Had to maintain multiple versions of a product?
Wanted to see the difference between two (or more) versions of your code?
Wanted to prove that a particula...
Is it possible to set the stacking order of pseudo-elements below their parent element? [duplicate]
...ange the default stacking order.
Positioning the pseudo-element (absolute) and assigning a z-index value other than “auto” creates the new stacking context.
#element {
position: relative; /* optional */
width: 100px;
height: 100px;
background-color: blue;
}
#elemen...
How to concatenate stdin and a string?
... pipe to accept stdout from echo "input" as stdin to another process / command:
echo "input" | awk '{print $1"string"}'
Output:
inputstring
What task are you exactly trying to accomplish? More context can get you more direction on a better solution.
Update - responding to comment:
@NoamRoss
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Why should I use Google's CDN for jQuery?
...This makes the time-to-download very small, because it is super compressed and it isn't compressed on the fly.)
It reduces the amount of bandwidth used by your server. (Google is basically offering free bandwidth.)
It ensures that the user will get a geographically close response. (Google has serv...
Git diff to show only lines that have been modified
... edited Sep 2 '15 at 17:24
Andrzej Rehmann
7,71366 gold badges3030 silver badges3535 bronze badges
answered Sep 15 '13 at 9:02
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What is the difference between join and merge in Pandas?
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I always use join on indices:
import pandas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l ...
execJs: 'Could not find a JavaScript runtime' but execjs AND therubyracer are in Gemfile
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Ubuntu Users:
I had the same problem and I fixed it by installing nodejson my system independent of the gem.
on ubuntu its: sudo apt-get install nodejs
I'm using 64bit ubuntu 11.10
update:
From @Galina 's answer below I'm guessing that the latest version of ...