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How to get distinct values for non-key column fields in Laravel?
...e this
$users = User::select('name')->groupBy('name')->get()->toArray() ;
groupBy is actually fetching the distinct values, in fact the groupBy will categorize the same values, so that we can use aggregate functions on them. but in this scenario we have no aggregate functions, we are ju...
Big-O for Eight Year Olds? [duplicate]
...ically, here are some good examples:
O(1): retrieving an element from an array. We know exactly where it is in memory, so we just go get it. It doesn't matter if the collection has 10 items or 10000; it's still at index (say) 3, so we just jump to location 3 in memory.
O(n): retrieving an element ...
Compare two objects' properties to find differences?
.../> object in the supplied List of
/// properties from the supplied Array of properties.
/// </summary>
/// <param name="allProperties">Array containing master list of
/// <see cref="PropertyInfo"/> objects.</param>
/// <param name="propertiesToRemo...
How to find indices of all occurrences of one string in another in JavaScript?
...,'gi');
var haystack = 'I learned to play the Ukulele';
var results = new Array();//this is the results you want
while (re.exec(haystack)){
results.push(re.lastIndex);
}
Edit: learn to spell RegExp
Also, I realized this isn't exactly what you want, as lastIndex tells us the end of the needle n...
How to join two JavaScript Objects, without using JQUERY [duplicate]
... Edition, ECMA-262):
Defined in several sections of the specification: Array Initializer, Argument Lists
Using this new syntax you could join/merge different objects into one object like this:
const result = {
...obj1,
...obj2,
};
5 - jQuery.extend(target, obj1, obj2):
Merge the conten...
Best practices for reducing Garbage Collector activity in Javascript
...ll(42)
When you call a builtin that does any of these under the hood, like Array.prototype.slice.
When you use arguments to reflect over the parameter list.
When you split a string or match with a regular expression.
Avoid doing those, and pool and reuse objects where possible.
Specifically, look...
Getting the name of the currently executing method
...ce information concerning this thread is permitted to return a zero-length array from this method.
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Inspect attached event handlers for any DOM element
...eners(document.getElementById("inputId")); but it returns invalid, with an array size of 1
– rich green
Sep 7 '17 at 3:09
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How to force file download with PHP
... = filesize($file);
$name = rawurldecode($name);
$known_mime_types=array(
"htm" => "text/html",
"exe" => "application/octet-stream",
"zip" => "application/zip",
"doc" => "application/msword",
"jpg" => "image/jpg",
"php" => "te...
Can you attach a UIGestureRecognizer to multiple views?
... ; frame = (0 44; 600 536); autoresize = RM+BM; gestureRecognizers = <NSArray...: >; layer = <CALayer: ...>>) at a time, this was never allowed, and is now enforced. Beginning with iOS 9.0 it will be put in the first view it is loaded into.
– George Brown
...