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Converting an array of objects to ActiveRecord::Relation
...ay of objects, let's call it an Indicator . I want to run Indicator class methods (those of the def self.subjects variety, scopes, etc) on this array. The only way I know to run class methods on a group of objects is to have them be an ActiveRecord::Relation. So I end up resorting to adding a to...
Is it possible to decrypt MD5 hashes?
Someone told me that he has seen software systems that:
24 Answers
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How to show all privileges from a user in oracle?
Can someone please tell me how to show all privileges/rules from a specific user in the sql-console?
6 Answers
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Multiple aggregations of the same column using pandas GroupBy.agg()
...uilt-in way to apply two different aggregating functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
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Is there a way to instantiate objects from a string holding their class name?
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Nope, there is none, unless you do the mapping yourself. C++ has no mechanism to create objects whose types are determined at runtime. You can use a map to do that mapping yourself, though:
template<typename T> Base * createInstance() { return new T; }
typedef std::map<std::string,...
Does setting Java objects to null do anything anymore?
I was browsing some old books and found a copy of "Practical Java" by Peter Hagger. In the performance section, there is a recommendation to set object references to null when no longer needed.
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How can I build a small operating system on an old desktop computer? [closed]
... have a firm understanding of how the OS works before you can hope to implement your own.
Grab one of Andrew Tanenbaum's books on operating systems. This is the one we used in my OS class in college:
Modern Operating Systems PDF
Modern Operating Systems on Amazon
Despite the ridiculous cov...
How do I set a variable to the output of a command in Bash?
I have a pretty simple script that is something like the following:
14 Answers
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Payment Processors - What do I need to know if I want to accept credit cards on my website? [closed]
This question talks about different payment processors and what they cost, but I'm looking for the answer to what do I need to do if I want to accept credit card payments?
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Memory management in Qt?
I'm quite new to Qt and am wondering on some basic stuff with memory management and the life of objects. When do I need to delete and/or destroy my objects? Is any of this handled automatically?
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