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Best way to test if a row exists in a MySQL table
...RE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything at all. MySQL
ignores the SELECT list in such a subquery, so it makes no difference.
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Android SDK installation doesn't find JDK
I'm trying to install the Android SDK on my Windows 7 x64 System.
45 Answers
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What is the Python equivalent of Matlab's tic and toc functions?
...e stuff
Sometimes I find this technique more convenient than timeit - it all depends on what you want to measure.
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Are HLists nothing more than a convoluted way of writing tuples?
I am really interested in finding out where the differences are, and more generally, to identify canonical use cases where HLists cannot be used (or rather, don't yield any benefits over regular lists).
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Specifically, what's dangerous about casting the result of malloc?
Now before people start marking this a dup, I've read all the following, none of which provide the answer I'm looking for:
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How to print a percentage value in python?
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Is float(1) really more pythonic than 1.?
– Tobias Kienzler
Jul 17 '13 at 7:58
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Finding quaternion representing the rotation from one vector to another
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Be aware that this does not handle the case of parallel vectors (both in the same direction or pointing in opposite directions). crossproduct will not be valid in these cases, so you first need to check dot(v1, v2) > 0.999999 and dot(v1, v2) < -0.999999, respectively, ...
Is it worth using Python's re.compile?
...uick glance at the actual Python 2.5 library code, I see that Python internally compiles AND CACHES regexes whenever you use them anyway (including calls to re.match()), so you're really only changing WHEN the regex gets compiled, and shouldn't be saving much time at all - only the time it takes to ...
Is there a function to make a copy of a PHP array to another?
...ewLarsson raises a point in the comments below. PHP has a special feature called "references". They are somewhat similar to pointers in languages like C/C++, but not quite the same. If your array contains references, then while the array itself is passed by copy, the references will still resolve to...
How to convert a String to its equivalent LINQ Expression Tree?
...nking as a Where clause. If necessary, put it inside a list/array just to call .Where(string) on it! i.e.
var people = new List<Person> { person };
int match = people.Where(filter).Any();
If not, writing a parser (using Expression under the hood) isn't hugely taxing - I wrote one similar (a...