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How do I create a unique constraint that also allows nulls?
I want to have a unique constraint on a column which I am going to populate with GUIDs. However, my data contains null values for this columns. How do I create the constraint that allows multiple null values?
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dynamic_cast and static_cast in C++
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Here's a rundown on static_cast<> and dynamic_cast<> specifically as they pertain to pointers. This is just a 101-level rundown, it does not cover all the intricacies.
static_cast< Type* >(ptr)
This takes the pointer in ptr and tries to safely cast it to a pointer of ty...
git rebase without changing commit timestamps
Would it make sense to perform git rebase while preserving the commit timestamps?
5 Answers
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What is HTML5 ARIA?
What is HTML5 ARIA? I do not understand how to implement it.
5 Answers
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Is it bad to have my virtualenv directory inside my git repository?
I'm thinking about putting the virtualenv for a Django web app I am making inside my git repository for the app. It seems like an easy way to keep deploy's simple and easy. Is there any reason why I shouldn't do this?
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support FragmentPagerAdapter holds reference to old fragments
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You are running into a problem because you are instantiating and keeping references to your fragments outside of PagerAdapter.getItem, and are trying to use those references independently of the ViewPager. As Seraph says, you do have guarantees tha...
How do I get a TextBox to only accept numeric input in WPF?
I'm looking to accept digits and the decimal point, but no sign.
31 Answers
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Find a string by searching all tables in SQL Server Management Studio 2008
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If you are like me and have certain restrictions in a production environment, you may wish to use a table variable instead of temp table, and an ad-hoc query rather than a create procedure.
Of course depending on your sql server instance, it must support table variables.
I als...
Difference between Visual Basic 6.0 and VBA
...at is the difference between the two. I always thought VBA is somewhat 'crippled' version of VB, but when a friend asked me the other day I had no idea what the actual differences are.
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How many parameters are too many? [closed]
Routines can have parameters, that's no news. You can define as many parameters as you may need, but too many of them will make your routine difficult to understand and maintain.
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