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Does MySQL ignore null values on unique constraints?
...sult:
x
NULL
NULL
1
This is not true for all databases. SQL Server 2005 and older, for example, only allows a single NULL value in a column that has a unique constraint.
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#ifdef in C#
...defined");
#elif (DEBUG && VC_V7)
Console.WriteLine("DEBUG and VC_V7 are defined");
#else
Console.WriteLine("DEBUG and VC_V7 are not defined");
#endif
}
}
Only useful for excluding parts of methods.
If you use #if to exclude some method from compilation then you will h...
What is the maximum float in Python?
...
Cool, both are very useful. inf for all things python, and float_info.max as a workaround when the earlier doesn't work, for example time.sleep(float("inf")) is not allowed :(
– Dima Tisnek
Oct 20 '16 at 11:27
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Android Studio - Where can I see callstack while debugging an android app?
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At the bottom panel you should have "5: Debug". Click on it and select "Debugger -> Threads"
You may need to find the "Threads" icon on the far right, or even click the "Restore Layout" button on the left to restore this window.
...
What is @RenderSection in asp.net MVC
What is the purpose of @RenderSection and how does it function? I understand what bundles do, but I have yet to figure out what this does and it's probably important.
...
What is the difference between the hidden attribute (HTML5) and the display:none rule (CSS)?
...rtaain cases you don't want it to be a part of the visual experience then handle it at the cosmetic layer. Bear in mind that some agents attempt to parse CSS and if they determine that something wouldn't be SEEN then they don't output it at all. I think this is aberrant behavior but it can help to k...
Android - Camera preview is sideways
...a.setParameters(parameters);
previewCamera();
}
And the previewCamera method :
public void previewCamera() {
try {
mCamera.setPreviewDisplay(mSurfaceHolder);
mCamera.startPreview();
isPreviewRunning = true;
} ca...
Javascript: Extend a Function
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With a wider view of what you're actually trying to do and the context in which you're doing it, I'm sure we could give you a better answer than the literal answer to your question.
But here's a literal answer:
If you're assigning these functions to some property somewhere, you...
How do I open links in Visual Studio in my web browser and not in Visual Studio?
...alled Open in External Browser. It works in Visual Studio 2012, 2013, 2015 and 2017. (An old version available on GitHub supports Visual Studio 2010.)
Thanks goes to Dmitry for pointing this out in his answer to this similar question.
EDIT: The Visual Studio team is finally starting to work on put...
.bashrc at ssh login
...ogue .bash_profile. It was created by the RVM install. I moved the RVM command to .profile and delete .bash_profile. All running fine now.
– Rod Daunoravicius
Oct 25 '13 at 10:02
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