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Entity Framework 4 Single() vs First() vs FirstOrDefault()
I'm having a devil of a time finding a comparison of the different ways to query for a single item, and when to use each.
6...
Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
Is it possible to specify your own distance function using scikit-learn K-Means Clustering?
8 Answers
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SQL JOIN vs IN performance?
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Generally speaking, IN and JOIN are different queries that can yield different results.
SELECT a.*
FROM a
JOIN b
ON a.col = b.col
is not the same as
SELECT a.*
FROM a
WHERE col IN
(
SELECT col
FROM b
)
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How do I hide an element on a click event anywhere outside of the element?
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If I understand, you want to hide a div when you click anywhere but the div, and if you do click while over the div, then it should NOT close. You can do that with this code:
$(document).click(function() {
alert("me");
}...
How to properly override clone method?
...one is broken.
Josh Bloch on Design - Copy Constructor versus Cloning
If you've read the item about cloning in my book, especially if you read between the lines, you will know that I think clone is deeply broken. [...] It's a shame that Cloneable is broken, but it happens.
You may read more d...
twig: IF with multiple conditions
It seem I have problem with a twig if statement.
1 Answer
1
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Fast Linux File Count for a large number of files
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By default ls sorts the names, which can take a while if there are a lot of them. Also there will be no output until all of the names are read and sorted. Use the ls -f option to turn off sorting.
ls -f | wc -l
Note that this will also enable -a, so ., .., and other files s...
Java Try Catch Finally blocks without Catch
...lock only. Since the catch block is excluded, how does the try block work if it encounters an exception or anything throwable? Does it just go directly to the finally block?
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Meaning of epsilon argument of assertEquals for double values
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@Emerald214 the amount of precision. If you want to assert that a double value is 0D epsilon would be 0 (100% accuracy, no exceptions). If you want a margin of error (say for degrees) you could set epsilon to 1 meaning that, for example, 64.2° is the same as 64...
Do I have to guard against SQL injection if I used a dropdown?
...ou expect.
$possibleOptions = array('All', 'Large', 'Medium', 'Small');
if(in_array($_POST['size'], $possibleOptions)) {
// Expected
} else {
// Not Expected
}
Then use mysqli_* if you are using a version of php >= 5.3.0 which you should be, to save your result. If used correctly thi...