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Does MySQL ignore null values on unique constraints?
I have an email column that I want to be unique. But I also want it to accept null values. Can my database have 2 null emails that way?
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How to use enum values in f:selectItem(s)
I want to make a selectOneMenu dropdown so I can select a status on my question. Is it possible to make the f:selectItem more flexible considering what happens if the order of the enums changes, and if the list was large? And could I do this better? And is it possible to automatically "select" the i...
When I catch an exception, how do I get the type, file, and line number?
Catching an exception that would print like this:
4 Answers
4
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omp parallel vs. omp parallel for
What is the difference between these two?
6 Answers
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What's the difference between == and .equals in Scala?
What is the difference between == and .equals() in Scala, and when to use which?
5 Answers
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What's the difference between Invoke() and BeginInvoke()
Just wondering what the difference between BeginInvoke() and Invoke() are?
6 Answers
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How to make the tab character 4 spaces instead of 8 spaces in nano?
When I press TAB in nano editor, the cursor will jump with 8 spaces like this:
6 Answers
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How to reduce iOS AVPlayer start delay
Note, for the below question: All assets are local on the device -- no network streaming is taking place. The videos contain audio tracks.
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When to use cla(), clf() or close() for clearing a plot in matplotlib?
Matplotlib offers there functions:
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