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Can PostgreSQL index array columns?
... to this question in the documentation. If a column is an array type, will all the entered values be individually indexed?
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In Django, how do I check if a user is in a certain group?
...add(group) # user is now in the "Editor" group
then user.groups.all() returns [<Group: Editor>].
Alternatively, and more directly, you can check if a a user is in a group by:
if django_user.groups.filter(name = groupname).exists():
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Note that groupname can also be the ac...
UIButton Image + Text IOS
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I see very complicated answers, all of them using code. However, if you are using Interface Builder, there is a very easy way to do this:
Select the button and set a title and an image. Note that if you set the background instead of the image then the ima...
Auto-center map with multiple markers in Google Maps API v3
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@MultiformeIngegno Calling it right after fitBounds worked for me in a brief test; let me know if you're still having trouble.
– metadept
Mar 30 '13 at 15:35
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Use logging print the output of pprint
...at much overhead that it's worth the trouble of adding the conditionals to all the DEBUG log statements?
– undefinedvariable
Sep 29 '15 at 13:04
2
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Objective-C categories in static library
...roject as direct dependency (target -> general -> direct dependencies) and all works OK, but categories. A category defined in static library is not working in app.
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Unioning two tables with different number of columns
... I realized that this solution also works without having to list all the columns. So instead of Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2, one can also do, Select *, Null as Col4, Null as Col5 from Table2.
– Pratik Patel
Sep 20 '...
Aren't Python strings immutable? Then why does a + “ ” + b work?
...the variable a to point at a new string "Dog eats treats". You didn't actually mutate the string "Dog". Strings are immutable, variables can point at whatever they want.
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How do you delete an ActiveRecord object?
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It's destroy and destroy_all methods, like
user.destroy
User.find(15).destroy
User.destroy(15)
User.where(age: 20).destroy_all
User.destroy_all(age: 20)
Alternatively you can use delete and delete_all which won't enforce :before_destroy and :after...
How can I view all the git repositories on my machine?
Is there a way in which I can see all the git repositories that exist on my machine? Any command for that?
10 Answers
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