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belongs_to through associations
Given the following associations, I need to reference the Question that a Choice is attached through from the Choice model. I have been attempting to use belongs_to :question, through: :answer to perform this action.
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What do I have to do to get Core Data to automatically migrate models?
I have read the documentation about automatic /lightweight migration for Core Data models - but I am having problems implementing it.
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Design Patterns web based applications [closed]
I am designing a simple web-based application. I am new to this web-based domain.I needed your advice regarding the design patterns like how responsibility should be distributed among Servlets, criteria to make new Servlet, etc.
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How to link to apps on the app store
I am creating a free version of my iPhone game. I want to have a button inside the free version that takes people to the paid version in the app store. If I use a standard link
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What does “program to interfaces, not implementations” mean?
...the client code always holds an Interface object which is supplied by a factory. Any instance returned by the factory would be of type Interface which any factory candidate class must have implemented. This way the client program is not worried about implementation and the interface signature determ...
Simplest way to profile a PHP script
What's the easiest way to profile a PHP script?
13 Answers
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Parse a .py file, read the AST, modify it, then write back the modified source code
I want to programmatically edit python source code. Basically I want to read a .py file, generate the AST , and then write back the modified python source code (i.e. another .py file).
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What are the underlying data structures used for Redis?
I'm trying to answer two questions in a definitive list:
3 Answers
3
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Why does NULL = NULL evaluate to false in SQL server
...erver if you have nullParam=NULL in a where clause, it always evaluates to false. This is counterintuitive and has caused me many errors. I do understand the IS NULL and IS NOT NULL keywords are the correct way to do it. But why does SQL server behave this way?
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What is the difference between atomic / volatile / synchronized?
How do atomic / volatile / synchronized work internally?
7 Answers
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