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Do rails rake tasks provide access to ActiveRecord models?
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namespace :test do
task :new_task => :environment do
puts Parent.all.inspect
end
end
Notice the => :environment dependency added to the task
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Data structure: insert, remove, contains, get random element, all at O(1)
... of the elements themselves as the keys.... I knew I was close, but this really nails it on the head!
– guildner
Apr 16 '11 at 6:36
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How to hide a in a menu with CSS?
I've realized that Chrome, it seems, will not allow me to hide <option> in a <select> . Firefox will.
13 Ans...
How does MySQL process ORDER BY and LIMIT in a query?
...not 1):
SELECT * FROM tbl LIMIT 5,10; # Retrieve rows 6-15
To retrieve all rows from a certain offset up to the end of the result set, you can use some large number for the second parameter. This statement retrieves all rows from the 96th row to the last:
SELECT * FROM tbl LIMIT 95,18446744073...
JOIN queries vs multiple queries
...ase. It depends on a lot of things. Jeff Atwood (founder of this site) actually wrote about this. For the most part, though, if you have the right indexes and you properly do your JOINs it is usually going to be faster to do 1 trip than several.
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Is floating-point math consistent in C#? Can it be?
...to way to make normal floating points deterministic in .net. The JITter is allowed to create code that behaves differently on different platforms(or between different versions of .net). So using normal floats in deterministic .net code is not possible.
The workarounds I considered:
Implement Fixe...
Is there a way to get rid of accents and convert a whole string to regular letters?
...f accents and making those letters regular apart from using String.replaceAll() method and replacing letters one by one?
Example:
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The way to check a HDFS directory's size?
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Prior to 0.20.203, and officially deprecated in 2.6.0:
hadoop fs -dus [directory]
Since 0.20.203 (dead link) 1.0.4 and still compatible through 2.6.0:
hdfs dfs -du [-s] [-h] URI [URI …]
You can also run hadoop fs -help for more info and specifics...
Constructing pandas DataFrame from values in variables gives “ValueError: If using all scalar values
...ipulate it to be index=[100], which works. Q: Isn't Index supposed to logically ordered incrementally, why does python allow Index manipulation?
– Sumanth Lazarus
Aug 2 '19 at 6:08
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Similar to jQuery .closest() but traversing descendants?
...found.length) break; // At least one match: break loop
// Get all children of the current set
$currentSet = $currentSet.children();
}
return $found.first(); // Return first match of the collection
}
})(jQuery);
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