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How do I manage MongoDB connections in a Node.js web application?

...there are multiple database.. should i open a connection for each database all together. If not, Is it OK to open and close when required? – Aman Gupta Oct 25 '16 at 14:19 ...
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How to get label of select option with jQuery?

The value can be retrieved by $select.val() . 11 Answers 11 ...
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What does an exclamation mark mean in the Swift language?

...pple have chosen to declare the types as implicitly unwrapped, making the calling code more convenient, but less safe. Perhaps Apple might comb through their frameworks in the future, removing the uncertainty of implicitly unwrapped ("probably never nil") parameters and replacing them with optional...
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What is the !! (not not) operator in JavaScript?

... Partial Obscurity: val.enabled = (userId != 0) ? true : false; // And finally, much easier to understand: val.enabled = (userId != 0); share | improve this answer | follow...
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What's “tools:context” in Android layout files?

... That attribute is basically the persistence for the "Associated Activity" selection above the layout. At runtime, a layout is always associated with an activity. It can of course be associated with more than one, but at least one. In the tool, we ...
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How to write an async method with out parameter?

... @orad I especially like this: private async Task<(bool success, Job job, string message)> TryGetJobAsync(...) – J. Andrew Laughlin Oct 26 '18 at 15:26 ...
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Close and Dispose - which to call?

...and Dispose in the case of SqlConnectionObject is: An application can call Close more than one time. No exception is generated. If you called Dispose method SqlConnection object state will be reset. If you try to call any method on disposed SqlConnection object, you will receive...
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How do disable paging by swiping with finger in ViewPager but still be able to swipe programmaticall

...tem(3); . But, I want to disable the paging by swiping with finger horizontally. Thus, the paging is done ONLY by clicking on the buttons. So, how I can disable the swiping with finger? ...
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Creating range in JavaScript - strange syntax

...guments How the Number function handles arguments What Function.prototype.call does They're rather advanced topics in javascript, so this will be more-than-rather long. We'll start from the top. Buckle up! 1. Why not just Array(5).map? What's an array, really? A regular object, containing intege...
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Calculate distance between two latitude-longitude points? (Haversine formula)

...a that the Wikipedia article uses? Is it more efficient and/or more numerically stable? – musiphil Dec 20 '12 at 3:47 ...