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Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
What are the rules for calling the superclass constructor?
What are the C++ rules for calling the superclass constructor from a subclass one?
10 Answers
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“java.lang.OutOfMemoryError : unable to create new native Thread”
...ing out of native threads, i.e. how many threads the operating system will allow your JVM to use.
This is an uncommon problem, because you rarely need that many. Do you have a lot of unconditional thread spawning where the threads should but doesn't finish?
You might consider rewriting into...
Giving UIView rounded corners
...ew controller's constructor, but rather in -viewDidLoad, after view is actually instantiated.
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Ruby on Rails: Delete multiple hash keys
...re unaware of the Hash#except method ActiveSupport adds to Hash.
It would allow your code to be simplified to:
redirect_to my_path(params.except(:controller, :action, :other_key))
Also, you wouldn't have to monkey patch, since the Rails team did it for you!
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Eclipse executable launcher error: Unable to locate companion shared library
I had Eclipse Indigo installed on my computer with the Android plugin and it was working perfectly for about two weeks. Today, I updated java and quicktime then restarted my computer. When it booted back up, eclipse had completely vanished - all the program files have completely disappeared. When I ...
System.Security.SecurityException when writing to Event Log
... ok on developer machines, where you do not use deployment process to install application.
However if you deploy your application to other machine(s), consider to register event log sources during installation as suggested in SailAvid's and Nicole Calinoiu's answers.
I am using PowerShell function...
Can I mix MySQL APIs in PHP?
...where. (Not sure whether plain old resources do that, but objects can actually take advantage of RAII to a not-insignificant degree.)
– cHao
Jul 5 '13 at 23:54
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In Vim is there a way to delete without putting text in the register?
...yboard layout I have to type "<space>_d. The space is needed to actually type the ".
– Sebastián Grignoli
Mar 12 '12 at 0:01
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Is there a __CLASS__ macro in C++?
Is there a __CLASS__ macro in C++ which gives the class name similar to __FUNCTION__ macro which gives the function name
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