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Ruby on Rails: getting the max value from a DB column
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Assuming your model name is Bar and it has a column named bar, this should work:
Bar.maximum("bar")
See the excellent Rails Guides section on Calculations for more info.
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Why do some C# lambda expressions compile to static methods?
As you can see in the code below, I have declared an Action<> object as a variable.
5 Answers
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printf() formatting for hex
This is more of a curious query than an important question, but why when printing hex as an 8 digit number with leading zeros, does this %#08X Not display the same result as 0x%08X ?
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In Python, how can you load YAML mappings as OrderedDicts?
I'd like to get PyYAML 's loader to load mappings (and ordered mappings) into the Python 2.7+ OrderedDict type, instead of the vanilla dict and the list of pairs it currently uses.
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What is the purpose of AsQueryable()?
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There are a few main uses.
As mentioned in other answers, you can use it to mock a queryable data source using an in-memory data source so that you can more easily test methods that will eventually be used on a non-enumerable based IQueryabl...
Android imageview not respecting maxWidth?
...t should display an arbitrary image, a profile picture downloaded from the internet. I want this the ImageView to scale its image to fit inside the height of the parent container, and a set max width of 60dip. However, if the image is tall ratio-wise, and doesn't need the full 60dip of width, the Im...
Implementing comparison operators via 'tuple' and 'tie', a good idea?
(Note: tuple and tie can be taken from Boost or C++11.)
When writing small structs with only two elements, I sometimes tend to choose a std::pair , as all important stuff is already done for that datatype, like operator< for strict-weak-ordering.
The downsides though are the pretty much us...
Undo “git add ”?
I mistakenly added files using the command "git add dir". I have not yet run "git commit". Is there a way to remove this dir and everything contained within it from the commit?
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Creating a left-arrow button (like UINavigationBar's “back” style) on a UIToolbar
I'd love to create a "back" left-arrow-bezel button in a UIToolbar .
24 Answers
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What does -fPIC mean when building a shared library?
I know the ' -fPIC ' option has something to do with resolving addresses and independence between individual modules, but I'm not sure what it really means. Can you explain?
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