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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(...
Remove border from IFrame
...ersson caniuse.com/#feat=iframe-seamless states that it isn't supported at all.
– Tim Büthe
Jun 19 '15 at 11:19
2
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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
...
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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Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
How is Perl's @INC constructed? (aka What are all the ways of affecting where Perl modules are searc
What are all the ways of affecting where Perl modules are searched for?
or, How is Perl's @INC constructed ?
3 Answers
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How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
Is there a way to call a block with a primitive parameter after a delay, like using performSelector:withObject:afterDelay: but with an argument like int / double / float ?
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Is it possible to set code behind a resource dictionary in WPF for event handling?
... behind: methods, properties and event handlers.
== Update for Windows 10 apps ==
And just in case you are playing with UWP there is one more thing to be aware of:
<Application x:Class="SampleProject.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
...
Standard alternative to GCC's ##__VA_ARGS__ trick?
...
It is possible to avoid the use of GCC's ,##__VA_ARGS__ extension if you are willing to accept some hardcoded upper limit on the number of arguments you can pass to your variadic macro, as described in Richard Hansen's answer to this question. If you do not want to hav...
to drawRect or not to drawRect (when should one use drawRect/Core Graphics vs subviews/images and wh
...bviews whenever you can. You can be more productive, and take advantage of all the OO mechanisms that should things easier to maintain. Use Core Graphics when you can't get the performance you need out of UIKit, or you know trying to hack together drawing effects in UIKit would be more complicated....