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What is the difference between UNION and UNION ALL?
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UNION removes duplicate records (where all columns in the results are the same), UNION ALL does not.
There is a performance hit when using UNION instead of UNION ALL, since the database server must do additional work to remove the duplicate rows, but usually you do not want ...
How to get JS variable to retain value after page refresh? [duplicate]
Is it possible to permanently change a javascript variable? As in, if I set the variable X and make that equal to 1. Then onClick of a button change that variable to 2. How can I get that variable to stay at 2 on refresh of the page?
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What would a “frozen dict” be?
I guess it could be something like collections.namedtuple , but that is more like a frozen-keys dict (a half-frozen dict). Isn't it?
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Floating point vs integer calculations on modern hardware
I am doing some performance critical work in C++, and we are currently using integer calculations for problems that are inherently floating point because "its faster". This causes a whole lot of annoying problems and adds a lot of annoying code.
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How do I restore a missing IIS Express SSL Certificate?
After setting up HTTPS in IIS Express, according to such articles as this and this , I am unable to actually load an IIS Express site using HTTPS. In Chrome , I am only getting:
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Better way to shuffle two numpy arrays in unison
I have two numpy arrays of different shapes, but with the same length (leading dimension). I want to shuffle each of them, such that corresponding elements continue to correspond -- i.e. shuffle them in unison with respect to their leading indices.
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libxml/tree.h no such file or directory
I am getting following errors.
22 Answers
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Is there a way to automatically generate getters and setters in Eclipse?
I am working on a new Android project ( Java ), and created an Object with a large number of variables. Since I am planning to add getters and setters for all of them, I was wondering: is there a shortcut in Eclipse for automatically generating the getters and setters in a given class?
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Is there a standard for storing normalized phone numbers in a database?
What is a good data structure for storing phone numbers in database fields? I'm looking for something that is flexible enough to handle international numbers, and also something that allows the various parts of the number to be queried efficiently.
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How do you match only valid roman numerals with a regular expression?
Thinking about my other problem , i decided I can't even create a regular expression that will match roman numerals (let alone a context-free grammar that will generate them)
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