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Django - limiting query results
...s are lazy. That means a query will hit the database only when you specifically ask for the result.
So until you print or actually use the result of a query you can filter further with no database access.
As you can see below your code only executes one sql query to fetch only the last 10 items.
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Make virtualenv inherit specific packages from your global site-packages
...ch will contain just some libraries (which i chose) of the base python installation.
4 Answers
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How do I avoid capturing self in blocks when implementing an API?
...ied inside the block (we're not doing that) but also they are not automatically retained when the block is retained (unless you are using ARC). If you do this, you must be sure that nothing else is going to try to execute the block after the MyDataProcessor instance is released. (Given the structure...
After array_filter(), how can I reset the keys to go in numerical order starting at 0
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If you call array_values on your array, it will be reindexed from zero.
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follo...
Why not use always android:configChanges=“keyboardHidden|orientation”?
...andle this myself. Yes, I know what I'm doing"
Is this a good thing? We shall soon see...
No worries?
One of the pros you start with is that there is:
no need to worry about your activity been rotated
In many cases, people mistakenly believe that when they have an error that is being genera...
PHP file_get_contents() and setting request headers
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Actually, upon further reading on the file_get_contents() function:
// Create a stream
$opts = [
"http" => [
"method" => "GET",
"header" => "Accept-language: en\r\n" .
"Cookie: foo=bar\r\...
Observer Design Pattern vs “Listeners”
It seems to me that the Observer design pattern as described in GOF is really the same thing as Listeners found in various toolkits. Is there a difference between the concepts, or are Listeners and Observers really the same thing.
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What's the equivalent for eclipse's ALT+UP/DOWN (move line) in Visual Studio?
...select a tag ? for example I have selected a div tag and I want to move up all child element , instead of selecting by mouse .
– Arash
Apr 17 '16 at 6:34
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How do you discover model attributes in Rails?
... am finding it difficult to easily see what attributes/properties exist on all of my model classes since they are not explicitly defined in my class files.
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Why prefer two's complement over sign-and-magnitude for signed numbers?
...o add them.
Two's complement addition is very simple. You add numbers normally and any carry bit at the end is discarded. So they're added as follows:
0010
+ 1111
=10001
= 0001 (discard the carry)
0001 is 1, which is the expected result of "2+(-1)".
But in your "intuitive" method, adding is m...