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Strings as Primary Keys in SQL Database [closed]
...ar with databases and the theories behind how they work. Is it any slower from a performance standpoint (inserting/updating/querying) to use Strings for Primary Keys than integers?
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std::next_permutation Implementation Explanation
...1 2 3 4
1 2 4 3
1 3 2 4
1 3 4 2
1 4 2 3
1 4 3 2
2 1 3 4
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How do we go from one permutation to the next? Firstly, let's look at things a little differently. We can view the elements as digits and the permutations as numbers. Viewing the problem in this way we want to order the permutations/numbe...
How do I center an SVG in a div?
...idly simple, but satisfying that it's of use to others as I have benefited from so many more sophisticated answers to questions here.
– David
Dec 6 '18 at 22:56
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Why is UnhandledExceptionEventArgs.ExceptionObject an object and not an Exception?
...xception because it's possible to throw objects in .Net that do not derive from System.Exception. This is not possible in C# or VB.Net but it is possible in other CLR based languages. Hence the API must support this possibility and uses the type object.
So while it shouldn't ever be null, it ma...
Can't access object property, even though it shows up in a console log
Below, you can see the output from these two logs. The first clearly shows the full object with the property I'm trying to access, but on the very next line of code, I can't access it with config.col_id_3 (see the "undefined" in the screenshot?). Can anyone explain this? I can get access to every ...
What is the apply function in Scala?
I never understood it from the contrived unmarshalling and verbing nouns ( an AddTwo class has an apply that adds two!) examples.
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How to get text box value in JavaScript
I am trying to use JavaScript to get the value from an HTML text box but value is not coming after white space
15 Answers
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JavaScript DOM remove element
...most browsers, there's a slightly more succinct way of removing an element from the DOM than calling .removeChild(element) on its parent, which is to just call element.remove(). In due course, this will probably become the standard and idiomatic way of removing an element from the DOM.
The .remove(...
How to use ConcurrentLinkedQueue?
...he queue? Or do I just have to define two methods (one to retrive elements from the list and another to add elements to the list)?
Note: obviously these two methods have to be synchronized. Right?
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How do CDI and EJB compare? interact?
...ations (Glassfish, JBoss AS, Websphere, etc).
EJB3 beans were retrofitted from the old legacy EJB2 component model* and were the first beans in Java EE to be managed beans via an annotation. EJB3 beans feature dependency injection, declarative transactions, declarative security, pooling, concurren...