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Does MySQL ignore null values on unique constraints?
... '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:
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.
...
How can I discard remote changes and mark a file as “resolved”?
.... is important; passing in a file name (in this case, the whole directory) selects between two different modes of operation of checkout, one which switches branches and one which moves files from the index to the working copy. I agree, it's very confusing. You could also do git checkout --ours -- &l...
Pure CSS to make font-size responsive based on dynamic amount of characters
...ntSize = "70%";
}
}
For me, I call this function when a user makes a selection in a drop-down, and then a div in my menu gets populated (this is where I have dynamic text occurring).
scaleFontSize("my_container_div");
In addition, I also use CSS ellipses ("...") to truncate yet even lon...
Sanitizing strings to make them URL and filename safe?
...OU
echo normal_chars('üÿÄËÏÖÜŸåÅ'); // uyAEIOUYaA
Based on the selected answer in this thread: URL Friendly Username in PHP?
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You have already activated X, but your Gemfile requires Y
...e exec is to uninstall the newer versions of rake.
$ gem uninstall rake
Select gem to uninstall:
1. rake-0.8.7
2. rake-0.9.2
3. All versions
> 2
Successfully uninstalled rake-0.9.2
This works, but if you are working with multiple apps that use different versions of rake, this can be a pai...
Numpy index slice without losing dimension information
...[0],[1,2]] you get the one dimensional array([2, 3]) My opinion is when selecting column or row vectors it's best to make the slice simple and then use np.reshape, So in my example it would be np.reshape(x[0,[1,2]],[1,2])
– Alexander
Sep 14 '15 at 1:43
...
What are some uses of decltype(auto)?
...
For non-generic code, like the initial example you gave, you can manually select to get a reference as a return type:
auto const& Example(int const& i)
{
return i;
}
but in generic code you want to be able to perfectly forward a return type without knowing whether you are dealing ...
How do you clear the focus in javascript?
...ect when using TypeScript, as you may not know the kind of element that is selected.
This would therefore be preferred:
if (document.activeElement instanceof HTMLElement)
document.activeElement.blur();
I would furthermore discourage using the solution provided in the accepted answer, as the ...
Detach many subdirectories into a new, separate Git repository
...sadjad, No idea, to be honest. The central point of the manual merge is to select the directories to form the new repo and keep their commit histories. I am not sure how to handle such situation where a commit put files into dirA, dirB, dirDrop and only dirA and dirB are chosen for the new repo, how...
How to clear the cache in NetBeans
...ee also http://wiki.netbeans.org/FaqWhatIsUserdir.
Help Menu
On Windows, selecting the Help » About menu will display a dialog that contains the following text:
Product Version: NetBeans IDE 8.0.2 (Build 201411181905)
Java: 1.7.0_80; Java HotSpot(TM) 64-Bit Server VM 24.80-b11
Runtime: Java(TM) ...