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How do I create a unique constraint that also allows nulls?
...e 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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Newline in string attribute
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Thanks! This solution fitted to my XAML-based serialization code very well.
– Seraphim
Jan 28 '17 at 14:11
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Why not inherit from List?
When planning out my programs, I often start with a chain of thought like so:
27 Answers
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Given a class, see if instance has method (Ruby)
...t method_defined means ONLY methods that you defined explicitly with:
def my_method
end
then read this:
In Ruby, a property (attribute) on your model is basically a method also. So method_defined? will also return true for properties, not just methods.
For example:
Given an instance of a class...
Android: Clear Activity Stack
I'm having several activities in my application. and flow is very complicated. When I click the Logout application navigates to login Screen and from there user can exit by cancel button (calling system.exit(0) )
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Best Practices: working with long, multiline strings in PHP?
...mple question but I'm somewhat obsessive compulsive over the formatting of my code.
10 Answers
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The current SynchronizationContext may not be used as a TaskScheduler
I am using Tasks to run long running server calls in my ViewModel and the results are marshalled back on Dispatcher using TaskScheduler.FromSyncronizationContext() . For example:
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Moving average or running mean
...hole thing in one loop, without dependencies, the code below works great.
mylist = [1, 2, 3, 4, 5, 6, 7]
N = 3
cumsum, moving_aves = [0], []
for i, x in enumerate(mylist, 1):
cumsum.append(cumsum[i-1] + x)
if i>=N:
moving_ave = (cumsum[i] - cumsum[i-N])/N
#can do stuff w...
How to convert java.sql.timestamp to LocalDate (java8) java.time?
...mment is extremely important here, hence the number of upvotes for it. See my answer for details stackoverflow.com/a/57101544/2032701
– Ruslan
Jul 18 '19 at 19:40
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Best practice for nested fragments in Android 4.0, 4.1 (
... getFragmentManager().beginTransaction().addFragment(R.id.frag_container, MyFragment.newInstance()).commit();
}
};
handler.post(runPager);
}
/**
* @see android.support.v4.app.Fragment#onPause()
*/
@Override
public void onPause()
{
super.onPause();
handler.removeCallbacks(...