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NOT IN vs NOT EXISTS
...cution plans may be the same at the moment but if either column is altered in the future to allow NULLs the NOT IN version will need to do more work (even if no NULLs are actually present in the data) and the semantics of NOT IN if NULLs are present are unlikely to be the ones you want anyway.
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How do you use variables in a simple PostgreSQL script?
For example, in MS-SQL, you can open up a query window and run the following:
10 Answers
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jQuery .on('change', function() {} not triggering for dynamically created inputs
The problem is that I have some dynamically created sets of input tags and I also have a function that is meant to trigger any time an input value is changed.
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jquery how to empty input field
I am in a mobile app and I use an input field in order user submit a number.
7 Answers
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Ways to save enums in database
What is the best way to save enums into a database?
11 Answers
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How to remove focus without setting focus to another control?
I like my UIs to be intuitive; each screen should naturally and unobtrusively guide the user on to the next step in the app. Barring that, I strive to make things as confusing and confounding as possible.
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How to pause a YouTube player when hiding the iframe?
I have a hidden div containing a YouTube video in an <iframe> . When the user clicks on a link, this div becomes visible, the user should then be able to play the video.
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Picking a random element from a set
How do I pick a random element from a set?
I'm particularly interested in picking a random element from a
HashSet or a LinkedHashSet, in Java.
Solutions for other languages are also welcome.
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Mongoose subdocuments vs nested schema
I'm curious as to the pros and cons of using subdocuments vs a deeper layer in my main schema:
6 Answers
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How to not wrap contents of a div?
I've got a fixed-width div with two buttons in it. If the labels of the buttons are too long, they wrap – one button stays on the first line, and the next button follows underneath it instead of adjacent to it.
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