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Difference between Django's annotate and aggregate methods?
Django's QuerySet has two methods, annotate and aggregate . The documentation says that:
3 Answers
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Why does int i = 1024 * 1024 * 1024 * 1024 compile without error?
...ere's nothing wrong with that statement; you're just multiplying 4 numbers and assigning it to an int, there just happens to be an overflow. This is different than assigning a single literal, which would be bounds-checked at compile-time.
It is the out-of-bounds literal that causes the error, not t...
Why is the String class declared final in Java?
...emented as immutable objects. You should read about immutability to understand more about it.
One advantage of immutable objects is that
You can share duplicates by pointing them to a single instance.
(from here).
If String were not final, you could create a subclass and have two strings tha...
Spring Expression Language (SpEL) with @Value: dollar vs. hash ($ vs. #)
... ${...} . Furthermore, when I started with SpEL I was told to use ${...} and it works fine.
4 Answers
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Rails detect if request was AJAX
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Warning: this does not work on standard remote: true calls in newer Rails versions, as the necessary headers don't get set.
– Roland Studer
May 27 at 18:04
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:first-child not working as expected
...1:first-child selector means
Select the first child of its parent
if and only if it's an h1 element.
The :first-child of the container here is the ul, and as such cannot satisfy h1:first-child.
There is CSS3's :first-of-type for your case:
.detail_container h1:first-of-type
{
color: bl...
Why is semicolon allowed in this python snippet?
...needs this semi-colon thing, but somebody thought it would be nice to have and added it to the language.
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round() for float in C++
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there is also lround and llround for integral results
– sp2danny
Feb 23 '15 at 11:55
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How do write IF ELSE statement in a MySQL query
...pression.
They look like this:
SELECT col1, col2, (case when (action = 2 and state = 0)
THEN
1
ELSE
0
END)
as state from tbl1;
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How do I hide javascript code in a webpage?
...ion directly which is code being viewed from the browser's View Source command.
As other have said, there is no way to protect javascript intended to run in a browser from a determined viewer. If the browser can run it, then any determined person can view/run it also.
But, if you put your javascr...