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Is there any difference between GROUP BY and DISTINCT
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MusiGenesis' response is functionally the correct one with regard to your question as stated; the SQL Server is smart enough to realize that if you are using "Group By" and not using any aggregate functions, then what you actually mean is "Distinct" - and therefore it generates a...
When should we use mutex and when should we use semaphore
... from a global linked list, you do not want another thread to muck around with pointers while you are deleting the node. When you acquire a mutex and are busy deleting a node, if another thread tries to acquire the same mutex, it will be put to sleep till you release the mutex.
Spinlock:
Use a spin...
Cache busting via params
...doing so. My thought was to apply a param to the end of css and js files with the current version number:
12 Answers
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Is it unnecessary to put super() in constructor?
Isn't this one automatically put by the compiler if I don't put it in a subclass's constructor?
6 Answers
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Looking to understand the iOS UIViewController lifecycle
...e appropriate times by iOS when you load/present/hide the view controller. It's important to note that these methods are attached to UIViewController and not to UIViews themselves. You won't get any of these features just using a UIView.
There's great documentation on Apple's site here. Putting in ...
Unable to start debugging because the object invoked has disconnected from its clients
...follow
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edited Apr 23 at 3:09
answered Oct 10 '14 at 6:29
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Check if element exists in jQuery [duplicate]
... me.
You need to put # before element id:
$('#elemId').length
---^
With vanilla JavaScript, you don't need the hash (#) e.g. document.getElementById('id_here') , however when using jQuery, you do need to put hash to target elements based on id just like CSS.
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Django 1.7 throws django.core.exceptions.AppRegistryNotReady: Models aren't loaded yet
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This is what solved it for us and these folks:
Our project started with Django 1.4, we went to 1.5 and then to 1.7. Our wsgi.py looked like this:
import os
from django.core.handlers.wsgi import WSGIHandler
os.environ['DJANGO_SETTINGS_MODULE'...
Difference between object and class in Scala
...object O creates a singleton object O as instance of some anonymous class; it can be used to hold static members that are not associated with instances of some class.
object O extends T makes the object O an instance of trait T; you can then pass O anywhere, a T is expected.
if there is a class C, t...
OAuth 2.0: Benefits and use cases — why?
Could anyone explain what's good about OAuth2 and why we should implement it? I ask because I'm a bit confused about it — here's my current thoughts:
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