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When do I use fabs and when is it sufficient to use std::abs?
...t, long, long long, std::intmax_t, float, double, long double. No short or char versions (or unsigned versions) that I can see.
– user673679
Mar 2 at 17:41
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MYSQL OR vs IN performance
...for future Googlers. Total count of returned results is 7264 out of 10000
SELECT * FROM item WHERE id = 1 OR id = 2 ... id = 10000
This query took 0.1239 seconds
SELECT * FROM item WHERE id IN (1,2,3,...10000)
This query took 0.0433 seconds
IN is 3 times faster than OR
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Unable to create a constant value of type Only primitive types or enumeration types are supported in
...umerable() // database query ends here, the rest is a query in memory
.Select(x =>
new PersonDTO
{
personId = x.personId,
addressId = x.addressId,
favoriteId = x.favoriteId,
personProtocol = ppCombined
.Where(p...
How to create a sequence of integers in C#?
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Linq projection with the rarely used indexer overload (i):
(new int[11]).Select((o,i) => i)
I prefer this method for its flexibilty.
For example, if I want evens:
(new int[11]).Select((item,i) => i*2)
Or if I want 5 minute increments of an hour:
(new int[12]).Select((item,i) => i*5...
Add 2 hours to current time in MySQL?
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SELECT *
FROM courses
WHERE DATE_ADD(NOW(), INTERVAL 2 HOUR) > start_time
See Date and Time Functions for other date/time manipulation.
share
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Combine :after with :hover
I want to combine :after with :hover in CSS (or any other pseudo selector). I basically have a list and the item with the selected class has an arrow shape applied using :after . I want the same to be true for objects that are being hovered over but cant quite get it to work. Heres the cod...
CSS “and” and “or”
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&& works by stringing-together multiple selectors like-so:
<div class="class1 class2"></div>
div.class1.class2
{
/* foo */
}
Another example:
<input type="radio" class="class1" />
input[type="radio"].class1
{
/* foo */
}
|| works by se...
Notepad++ add to every line
...first line
Hold down Alt + Shift and use the cursor down key to extend the selection to the end of the block
This allows you to type on every line simultaneously.
I found the solution above here.
I think this is much easier than using regex.
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How to get nth jQuery element
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Why not browse the (short) selectors page first?
Here it is: the :eq() operator. It is used just like get(), but it returns the jQuery object.
Or you can use .eq() function too.
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Show an image preview before upload
... code snippet in the HTML example below filters out images from the user's selection and renders selected files into multiple thumbnail previews:
function handleFileSelect(evt) {
var files = evt.target.files;
// Loop through the FileList and render image files as thumbnails.
fo...