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SQL: How to properly check if a record exists
...optimize SELECT COUNT(*) anyway, so while there is a difference in theory (and older databases), you shouldn't notice any difference in practice.
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How Big can a Python List Get?
...ognize them because of the asterix at the end) . Pointers are 4 bytes long and store a memory address to the allocated object. They are "only" 4 bytes long because with 4 bytes you can address every element in a memory of nowadays computers.
– Antonio Ragagnin
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How can I generate a diff for a single file between two branches in github
... me to do this for all changed files, but that's no good as there are thousands of files in my repo.
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Modifying location.hash without page scrolling
We've got a few pages using ajax to load in content and there's a few occasions where we need to deep link into a page. Instead of having a link to "Users" and telling people to click "settings" it's helpful to be able to link people to user.aspx#settings
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Which is generally best to use — StringComparison.OrdinalIgnoreCase or StringComparison.InvariantCul
...wners previously using the InvariantCulture for string comparison, casing, and sorting should strongly consider using a new set of String overloads in Microsoft .NET 2.0. Specifically, data that is designed to be culture-agnostic and linguistically irrelevant should begin specifying overloads using ...
how to reset
I am developing a metro app with VS2012 and Javascript
27 Answers
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Where can I learn how to write C code to speed up slow R functions? [closed]
...for learning how to write C code for use with R? I know about the system and foreign language interfaces section of R extensions, but I find it pretty hard going. What are good resources (both online and offline) for writing C code for use with R?
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how do i block or restrict special characters from input fields with jquery?
...l allowed for the use of control characters (e.g., backspace, delete, tab) and copy+paste. None of the provided answers that I tried satisfied all of these requirements, so I came up with the following using the input event.
$('input').on('input', function() {
$(this).val($(this).val().replace(/[...
Test whether a list contains a specific value in Clojure
...se for sets (which can be thought of as making no distinction between keys and values), maps (so (contains? {:foo 1} :foo) is true) and vectors (but note that (contains? [:foo :bar] 0) is true, because the keys here are indices and the vector in question does "contain" the index 0!).
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On select change, get data attribute value
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I've just come across this and I am wondering if the first method is preferred due to performance reasons, or another reason? @JordanBrown
– Clarkey
Aug 19 '15 at 15:31
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