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Does MySQL ignore null values on unique constraints?
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NULL
NULL
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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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$(window).scrollTop() vs. $(document).scrollTop()
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@d2burke scrollTop() is a getter and scrollTop(value) is a setter. scrollTop() without arguments does not change the scroll position.
– user1107907
Feb 19 '15 at 22:20
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JavaScript arrays braces vs brackets
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The first and third are equivalent and create a new array. The second creates a new empty object, not an array.
var myArray = []; //create a new array
var myArray = {}; //creates **a new empty object**
var myArray = new Array(); //cre...
Understand homebrew and keg-only dependencies
I've recently started using homebrew, and I'm a bit confused as to what happens when I brew something onto my system, but its brewed dependencies are keg-only, meaning that they are linked under /usr/local .
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Programmatically shut down Spring Boot application
... @StackOverFlow You need to inject the bean where you need it and then pass the return code as you suggested (x=0) if it's shutting down correctly. For example you could inject the Shutdown Manager into a RestController and allow remote shutdown, or you could inject it into a healthchec...
How to reload page every 5 seconds?
... answered May 7 '10 at 10:03
jAndyjAndy
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Cannot use object of type stdClass as array?
...$result->context = $var) This causes the property to be set to the var and returns true, no matter.
– STWilson
Nov 16 '16 at 21:28
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What is the purpose of the Visual Studio Hosting Process?
...e the Visual Studio hosting process . What is this purpose of this option and what effect does it have?
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How can I select item with class within a DIV?
... context.
Good to learn from the find() documentation:
The .find() and .children() methods are similar, except that the
latter only travels a single level down the DOM tree.
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Can you supply arguments to the map(&:method) syntax in Ruby?
You're probably familiar with the following Ruby shorthand ( a is an array):
7 Answers
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