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Validate uniqueness of multiple columns
Is there a rails-way way to validate that an actual record is unique and not just a column? For example, a friendship model / table should not be able to have multiple identical records like:
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In Java, are enum types inside a class static?
I can't seem to access instance members of the surrounding class from inside an enum, as I could from inside an inner class. Does that mean enums are static? Is there any access to the scope of the surrounding class's instance, or do I have to pass the instance into the enum's method where I need it...
Populate XDocument from String
I'm working on a little something and I am trying to figure out whether I can load an XDocument from a string. XDocument.Load() seems to take the string passed to it as a path to a physical XML file.
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What does the forward slash mean in the CSS font shorthand?
I'm seeing the following CSS declaration in a stylesheet:
2 Answers
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How to prevent errno 32 broken pipe?
Currently I am using an app built in python. When I run it in personal computer, it works without problems.
4 Answers
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How to use greater than operator with date?
No idea what is going on here. Here is the query, right from phpMyAdmin:
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5
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How to write an XPath query to match two attributes?
Following Question:
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4
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Incorrect syntax near ')' calling stored procedure with GETDATE
Maybe I am having a moment of 'afternoon', but can anyone explain why I get
2 Answers
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Java “params” in method signature?
In C#, if you want a method to have an indeterminate number of parameters, you can make the final parameter in the method signature a params so that the method parameter looks like an array but allows everyone using the method to pass as many parameters of that type as the caller wants.
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