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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...if you DON'T have an index (as it doesn't sort). When you do have an index and it's used, they're synonyms.
– Quassnoi
Feb 27 '09 at 15:11
10
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What is the difference between the add and offer methods in a Queue in Java?
... element can not be added to collection the add method throws an exception and offer doesn't.
From: http://java.sun.com/j2se/1.5.0/docs/api/java/util/Collection.html#add%28E%29
If a collection refuses to add a
particular element for any reason
other than that it already contains
the eleme...
How to use NSJSONSerialization
..."id": "2", "name":"Bbb"}]
This might give you a clear picture of how to handle it:
NSError *e = nil;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: data options: NSJSONReadingMutableContainers error: &e];
if (!jsonArray) {
NSLog(@"Error parsing JSON: %@", e);
} else {
for...
How to efficiently compare two unordered lists (not sets) in Python?
... Hey @Raymond, I recently encountered this question on an interview and I used sorted(), admittedly not knowing about Counter. The interviewer insisted there was a more efficient method and clearly I drew a blank. After extensive testing in python 3 with the timeit module, sorted consisten...
Difference between len() and .__len__()?
...y calling an object's __len__ method. __something__ attributes are special and usually more than meets the eye, and generally should not be called directly.
It was decided at some point long ago getting the length of something should be a function and not a method code, reasoning that len(a)'s mean...
Javascript calculate the day of the year (1 - 366)
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Edit: The code above will fail when now is a date in between march 26th and October 29th andnow's time is before 1AM (eg 00:59:59). This is due to the code not taking daylight savings time into account. You should compensate for this:
var now = new Date();
var start = new Date(now.getFullY...
Xcode Debugger: view value of variable
... answered Jan 19 '11 at 15:15
AndriyAndriy
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How to reset a form using jQuery with .reset() method
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Simply magical and straight forward! Much appreciated for sharing.
– Ajay Kumar
Dec 10 '18 at 19:38
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Firebug says “No Javascript on this page”, even though JavaScript does exist on the page
...functionality but Firebug per se is never going to be fixed for Firefox 50 and beyond
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How to merge specific files from Git branches
I have 2 git branches branch1 and branch2 and I want to merge file.py in branch2 into file.py in branch1 and only that file.
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