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Fastest way to get the first object from a queryset in django?
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also, first() and last() enforce an ORDER BY clause on a query. It will make the results deterministic but will most probably slow the query down.
– Phil Krylov
Jun 27 '17 at 19:24
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Why should I use version control? [closed]
...re "advanced" features like branching and merging let you have multiple parallel lines of development. You can work in two simultaneous features without interference and switch back and forth without much hassle.
You can see "what changed". This may sound basic, but that's something I find myself ch...
Is Big O(logn) log base e?
... big-O notation is usually written showing only the asymptotically highest order of n, so constant coefficients will drop away. Since a different logarithm base is equivalent to a constant coefficient, it is superfluous.
That said, I would probably assume log base 2.
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Why is Node.js single threaded? [closed]
...Converting product data into a UI is not CPU intensive, nor is calculating orders or the like. Most of the web is pretty transactional. CPU intensive stuff is things like converting videos, converting image formats, etc. Much of that is due to file i/o which, actually, node does pretty well. And...
What are the applications of binary trees?
...tures. That's because, unless the data is coming in in a relatively random order, the tree can easily degenerate into its worst-case form, which is a linked list, since simple binary trees are not balanced.
A good case in point: I once had to fix some software which loaded its data into a binary tr...
Push existing project into Github
...re rejected because the remote contains work that you do
hint: not have locally. This is usually caused by another repository pushing
hint: to the same ref. You may want to first merge the remote changes (e.g.,
hint: 'git pull') before pushing again.
hint: See the 'Note about fast-forwards' in 'git ...
How to know if two arrays have the same values
...n compare their joined strings to see if they have the same members in any order-
var array1= [10, 6, 19, 16, 14, 15, 2, 9, 5, 3, 4, 13, 8, 7, 1, 12, 18, 11, 20, 17];
var array2= [12, 18, 20, 11, 19, 14, 6, 7, 8, 16, 9, 3, 1, 13, 5, 4, 15, 10, 2, 17];
if(array1.sort().join(',')=== array2.sort().jo...
Prevent BODY from scrolling when a modal is opened
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In order to fix scrolling to top, you can record position before adding the class, then after class is removed, do window.scroll to recorded position. This is how I fixed it for myself: pastebin.com/Vpsz07zd.
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Centering a background image, using CSS
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screenshot - imagevat.com/picview.php?ig=6179 I am not sure how to upload images to jsfiddle, if you can help me out there jsfiddle.net/yWrQP
– X10nD
Apr 15 '10 at 7:52
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in_array multiple values
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if(count(array_intersect($haystack, $target)) == count($target)){
// all of $target is in $haystack
}
Note that you only need to verify the size of the resulting intersection is the same size as the array of target values to say that $haystack is a superset of $target.
To verify that at lea...