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Count(*) vs Count(1) - SQL Server
Just wondering if any of you people use Count(1) over Count(*) and if there is a noticeable difference in performance or if this is just a legacy habit that has been brought forward from days gone past?
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Difference between “and” and && in Ruby?
What is the difference between the && and and operators in Ruby?
7 Answers
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Get type of all variables
...R, I'd like to retrieve a list of global variables at the end of my script and iterate over them. Here is my code
6 Answers...
What is the advantage to using bloom filters?
I am reading up on bloom filters and they just seem silly. Anything you can accomplish with a bloom filter, you could accomplish in less space, more efficiently, using a single hash function rather than multiple, or that's what it seems. Why would you use a bloom filter and how is it useful?
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Does Java 8 provide a good way to repeat a value or function?
...- 1)
.forEach(System.out::println);
Or build a custom iteration and limit the size of the iteration:
IntStream.iterate(1, i -> i + 2)
.limit(8)
.forEach(System.out::println);
share
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Android emulator-5554 offline
... order to be assured that your emulator starts working again :
Go to cmd and type adb kill-server
Go to task manager and find adb in processes. If you find one, right click on it and click on end process tree.
In eclipse, go to Window>Android Virtual Device Manager, click on the AVD you want t...
Difference between dispatch_async and dispatch_sync on serial queue?
...k is finished whereas dispatch_async return after it is added to the queue and may not finished.
for this code
dispatch_async(_serialQueue, ^{ printf("1"); });
printf("2");
dispatch_async(_serialQueue, ^{ printf("3"); });
printf("4");
It may print 2413 or 2143 or 1234 but 1 always before 3
for ...
Understanding dict.copy() - shallow or deep?
... 3, 4, 5]}, {1: [1, 2, 3, 4]})
So:
b = a: Reference assignment, Make a and b points to the same object.
b = a.copy(): Shallow copying, a and b will become two isolated objects, but their contents still share the same reference
b = copy.deepcopy(a): Deep copying, a and b's structure and conte...
Difference between Pragma and Cache-Control headers?
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Pragma is the HTTP/1.0 implementation and cache-control is the HTTP/1.1 implementation of the same concept. They both are meant to prevent the client from caching the response. Older clients may not support HTTP/1.1 which is why that header is still in use.
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Remove duplicate values from JS array [duplicate]
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Quick and dirty using jQuery:
var names = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"];
var uniqueNames = [];
$.each(names, function(i, el){
if($.inArray(el, uniqueNames) === -1) uniqueNames.push(el);
});
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