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How to create a unique index on a NULL column?
...rver 2005. I want to constrain the values in a column to be unique, while allowing NULLS.
4 Answers
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What is the difference between shallow copy, deepcopy and normal assignment operation?
...ble towards the existing object. The docs explain the difference between shallow and deep copies:
The difference between shallow and deep copying is only relevant for
compound objects (objects that contain other objects, like lists or
class instances):
A shallow copy constructs a new...
E731 do not assign a lambda expression, use a def
...rst form means that the name of the resulting
function object is specifically 'f' instead of the generic '<lambda>'.
This is more useful for tracebacks and string representations in
general. The use of the assignment statement eliminates the sole
benefit a lambda expression can offer o...
How do CUDA blocks/warps/threads map onto CUDA cores?
I have been using CUDA for a few weeks, but I have some doubts about the allocation of blocks/warps/thread.
I am studying the architecture from a didactic point of view (university project), so reaching peak performance is not my concern.
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How to securely store access token and secret in Android?
...other apps cannot access them. On a rooted devices, if the user explicitly allows access to some app that is trying to read them, the app might be able to use them, but you cannot protect against that. As for encryption, you have to either require the user to enter the decrypt passphrase every time ...
Is there a way to cache GitHub credentials for pushing commits?
...itched to synchronizing my repositories to https:// on GitHub (due to firewall issues), and it asks for a password every time.
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HEAD and ORIG_HEAD in Git
..., and it is a commit on top of which "git commit" would make a new one. Usually HEAD is symbolic reference to some other named branch; this branch is currently checked out branch, or current branch. HEAD can also point directly to a commit; this state is called "detached HEAD", and can be understood...
Same-named attributes in attrs.xml for custom view
...tyleable> com_app_view_widget, unable to find attribute customAttr For all the view I try to declare for. Any ideas?
– Dapp
Jun 9 '14 at 14:54
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What's the difference between :: (double colon) and -> (arrow) in PHP?
... used to access static members, such usage is discouraged), while :: is usually used to access static members (though in a few special cases, it's used to access instance members).
In general, :: is used for scope resolution, and it may have either a class name, parent, self, or (in PHP 5.3) static...
When should I use malloc in C and when don't I?
I understand how malloc() works. My question is, I'll see things like this:
6 Answers
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