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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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How to check if running as root in a bash script
I'm writing a script that requires root level permissions, and I want to make it so that if the script is not run as root, it simply echoes "Please run as root." and exits.
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Isn't it silly that a tiny favicon requires yet another HTTP request? How can I put the favicon into
...asked, because until fairly recently, most browsers have not been able to handle favicons in .svg format.
That's not the case anymore.
See: https://caniuse.com/#feat=link-icon-svg
1) Choose SVG as the Favicon format
Right now, in June 2020, these browsers can handle SVG Favicons:
Chrome
Firefox
Ed...
Escaping quotes and double quotes
...do I properly escape the quotes in the -param value in the following command line?
3 Answers
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How can we programmatically detect which iOS version is device running on? [duplicate]
I want to check if the user is running the app on iOS less than 5.0 and display a label in the app.
10 Answers
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How to get error information when HttpWebRequest.GetResponse() fails
I am initiating an HttpWebRequest and then retrieving it's response. Occasionally, I get a 500 (or at least 5##) error, but no description. I have control over both endpoints and would like the receiving end to get a little bit more information. For example, I would like to pass the exception mes...
What is the benefit of using $() instead of backticks in shell scripts?
There are two ways to capture the output of command line in bash :
8 Answers
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How do I autoindent in Netbeans?
In eclipse you can click Ctrl + I at any line, and it'll automatically indent the line or group of lines according to the indentation scheme you chose in the settings.
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What's the difference between ngModel.$modelValue and ngModel.$viewValue
...tion, but it might just be that you're a little confused. The $modelValue and $viewValue have one distinct difference. It is this:
As you already noted above:
$viewValue: Actual string (or Object) value in the view.
$modelValue: The value in the model, that the control is bound to.
I'm go...
How do you update Xcode on OSX to the latest version?
...Store
Look in the top right for the updates section (may also be in lefthand column "Updates"..)
Find Xcode & click Update
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