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SQL Joins Vs SQL Subqueries (Performance)?
...PECT the first query to be quicker, mainly because you have an equivalence and an explicit JOIN. In my experience IN is a very slow operator, since SQL normally evaluates it as a series of WHERE clauses separated by "OR" (WHERE x=Y OR x=Z OR...).
As with ALL THINGS SQL though, your mileage may va...
When would you use a List instead of a Dictionary?
What is the difference between a List of KeyValuePair and a Dictionary for the same types? Is there an appropriate time to use one or the other?
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What can MATLAB do that R cannot do? [closed]
...hey have much more in common than not. It partially depends on your field and use-case. And as Spencer Graves said previously, it also depends on which "church you happen to frequent". It's best if you look at the MATLAB toolkit vs. CRAN for a specific task before you decide.
A similar questio...
Understanding recursion [closed]
I'm having major trouble understanding recursion at school. Whenever the professor is talking about it, I seem to get it but as soon as I try it on my own it completely blows my brains.
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How do I convert a dictionary to a JSON String in C#?
...ld be better off using a reputable JSON library that already knows how to handle things like escape characters and line breaks. Json.NET is a popular option.
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Shortcut to open file in Vim
...ption of autofill. Invoke a keyboard shortcut, type the file name/pattern, and choose from all the matching files names.
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HtmlSpecialChars equivalent in Javascript?
Apparently, this is harder to find than I thought it would be. And it even is so simple...
16 Answers
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Calculating moving average
... R not containing future values of given timestamp? I checked forecast::ma and it contains all neighbourhood, not right.
– hhh
Sep 7 '18 at 20:52
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How do I remove a property from a JavaScript object?
...edibly in-depth blog post about the delete statement on their blog, Understanding delete. It is highly recommended.
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Java equivalents of C# String.Format() and String.Join()
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More precisely: StringBuffer for jdk1.4 and below, StringBuilder for jdk1.5 and after, since the latter is not synchronized, hence a little faster.
– VonC
Oct 9 '08 at 15:39
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