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Django filter versus get for single object?
...es try/except (see EAFP), that's why QS.get() is good. 2. Details matter: does "expecting only one" means always 0-1 objects, or it's possible to have 2+ objects and that case should be handled too (in this case len(objs) is a terrible idea)? 3. Don't assume anything about overhead without a bench...
Fastest way to determine if record exists
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Doesn't optimizer take it into account itself when searches through PK (or any other unique key)?
– zerkms
Aug 7 '13 at 21:56
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How can I maintain fragment state when added to the back stack?
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If you return to a fragment from the back stack it does not re-create the fragment but re-uses the same instance and starts with onCreateView() in the fragment lifecycle, see Fragment lifecycle.
So if you want to store state you should use instance variables and not rely on...
For-each over an array in JavaScript
... and a reference to the array you're iterating over (in case your function doesn't already have it handy).
Unless you're supporting obsolete browsers like IE8 (which NetApps shows at just over 4% market share as of this writing in September 2016), you can happily use forEach in a general-purpose w...
Check whether variable is number or string in JavaScript
Does anyone know how can I check whether a variable is a number or a string in JavaScript?
32 Answers
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How to recursively delete an entire directory with PowerShell 2.0?
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Remove-Item -Recurse -Force some_dir
does indeed work as advertised here.
rm -r -fo some_dir
are shorthand aliases that work too.
As far as I understood it, the -Recurse parameter just doesn't work correctly when you try deleting a filtered set of files recu...
In PHP with PDO, how to check the final SQL parametrized query? [duplicate]
...for this.
Short Answer
As mentioned by Ben James: NO.
The full SQL query does not exist on the PHP side, because the query-with-tokens and the parameters are sent separately to the database.
Only on the database side the full query exists.
Even trying to create a function to replace tokens on the...
Removing the fragment identifier from AngularJS urls (# symbol)
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Because IE lt 10 doesn't support html5 history API which were enabled by setting up html5Mode(true). In IE you have to use # in routes.
– Maxim Grach
Feb 8 '13 at 16:50
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Vim indent xml file
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Why does everybody expect there is an xmllint tool? In Ubuntu 15.04 there isn't and apt-get also can't find one.
– erikbwork
May 18 '15 at 12:01
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Is there a limit to the length of a GET request? [duplicate]
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Not in the RFC, no, but there are practical limits.
The HTTP protocol does not place any a priori limit on the length of
a URI. Servers MUST be able to handle the URI of any resource they
serve, and SHOULD be able to handle URIs of unbounded length if they
provide GET-based forms that could gen...