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In Django, how do I check if a user is in a certain group?
...roup for this example
user = User.objects.get(pk = 1) # assuming, there is one initial user
user.groups.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:
i...
Codesign error: Certificate identity appearing twice
CodeSign error: Certificate identity 'iPhone Developer: XXXX (12345678)' appears more than once in the keychain. The codesign tool requires there only be one.
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Prevent users from submitting a form by hitting Enter
...fix, and don't have time to implement validation items. I appreciate everyone's answers, but this is the one i'm going to go with in the mean time. thank you.
– DForck42
May 22 '09 at 13:42
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Difference between DateTime and Time in Ruby
...Time and Time classes in Ruby and what factors would cause me to choose one or the other?
7 Answers
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Good PHP ORM Library?
...hands down the best database abstraction layer i've ever worked with. not "one of the best" - the best.
– Nir Gavish
Feb 15 '10 at 18:15
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Are Java static calls more or less expensive than non-static calls?
Is there any performance benefit one way or another? Is it compiler/VM specific? I am using Hotspot.
12 Answers
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DateTime vs DateTimeOffset
...rently, we have a standard way of dealing with .NET DateTime 's in a TimeZone aware way: Whenever we produce a DateTime we do it in UTC (e.g. using DateTime.UtcNow ), and whenever we display one, we convert back from UTC to the user's local time.
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ROW_NUMBER() in MySQL
...gle highest col3 for each (col1, col2) pair.
That's a groupwise maximum, one of the most commonly-asked SQL questions (since it seems like it should be easy, but actually it kind of isn't).
I often plump for a null-self-join:
SELECT t0.col3
FROM table AS t0
LEFT JOIN table AS t1 ON t0.col1=t1.co...
Maximum single-sell profit
...halves. If we think about what the optimal answer might be, it must be in one of three places:
The correct buy/sell pair occurs completely within the first half.
The correct buy/sell pair occurs completely within the second half.
The correct buy/sell pair occurs across both halves - we buy in the...
Loaded nib but the 'view' outlet was not set
... XIB file causing problems
Click on file's owner icon on the left bar (top one, looks like a yellow outlined box)
If you don't see the right-hand sidebar, click on the third icon above "view" in your toolbar. This will show the right-hand sidebar
In the right-hand sidebar, click on the third tab--th...