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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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Should I instantiate instance variables on declaration or in the constructor?
Is there any advantage for either approach?
15 Answers
15
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A generic error occurred in GDI+, JPEG Image to MemoryStream
This seems to be a bit of an infamous error all over the web. So much so that I have been unable to find an answer to my problem as my scenario doesn't fit. An exception gets thrown when I save the image to the stream.
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When to use the different log levels
There are different ways to log messages, in order of fatality:
18 Answers
18
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What does “where T : class, new()” mean?
Can you please explain to me what where T : class, new() means in the following line of code?
11 Answers
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Is there a standardized method to swap two variables in Python?
In Python, I've seen two variable values swapped using this syntax:
7 Answers
7
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How do I add the contents of an iterable to a set?
What is the "one [...] obvious way" to add all items of an iterable to an existing set ?
6 Answers
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What are some examples of commonly used practices for naming git branches? [closed]
I've been using a local git repository interacting with my group's CVS repository for several months, now. I've made an almost neurotic number of branches, most of which have thankfully merged back into my trunk. But naming is starting to become an issue. If I have a task easily named with a simp...
How to remove non-alphanumeric characters?
I need to remove all characters from a string which aren't in a-z A-Z 0-9 set or are not spaces.
9 Answers
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getApplication() vs. getApplicationContext()
I couldn't find a satisfying answer to this, so here we go: what's the deal with Activity/Service.getApplication() and Context.getApplicationContext() ?
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