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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: https://docs.djangoproje...
Can I store the .git folder outside the files I want tracked?
...ckup and Git will pick them up on each command. That will only comfortably allow you to work in a single repository per shell, though.
I’d rather suggest symlinking the .git directory to somewhere else, or creating a symlink to the .git directory from your main backup directory.
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How can I get Git to follow symlinks?
...o store symlinks instead of following them (for compactness, and it's generally what people want).
However, I accidentally managed to get it to add files beyond the symlink when the symlink is a directory.
I.e.:
/foo/
/foo/baz
/bar/foo --> /foo
/bar/foo/baz
by doing
git add /bar/fo...
How to check for an undefined or null variable in JavaScript?
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@SharjeelAhmed It is mathematically corrected. NaN from difference equation can never expected to be equal
– Thaina
Oct 4 '19 at 4:12
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Different ways of adding to Dictionary
...if it does and the parameter add is true, it throws the exception.
So for all purposes and intents the performance is the same.
Like a few other mentions, it's all about whether you need the check, for attempts at adding the same key twice.
Sorry for the lengthy post, I hope it's okay.
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Create directory if it does not exist
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What will -Force actually do? The documentation says "Forces this cmdlet to create an item that writes over an existing read-only item". Will it delete an existing folder? It should be clear in this answer.
– Peter Mortensen...
How can I use Timer (formerly NSTimer) in Swift?
...ctor(eventWith(timer:)),
userInfo: [ "foo" : "bar" ],
repeats: true)
}
// Timer expects @objc selector
@objc func eventWith(timer: Timer!) {
let info = timer.userInfo as Any
print(info)
}
}
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Casting to string in JavaScript
... searched for those three options in the jQuery source code, and they are all in use .
I would like to know if there are any differences between them:
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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
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If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its type, the behavior is undefined. [ Note: most existing implementations of C++
ignore integer overflows. Treatment of division by zero, forming a remainde...
How do I merge two javascript objects together in ES6+?
.../en-US/docs/Web/JavaScript/Reference/… Running babel-node: const ob1 = {foo: 123}; const ob2 = {bar: 234}; const merged = {...ob1, ...ob2}; console.log(merged) Output: { foo: 123, bar: 234 }
– Thijs Koerselman
Sep 4 '15 at 18:52
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