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Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign
I make an outer join and executed successfully in the informix database but I get the following exception in my code:
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How do you split a list into evenly sized chunks?
...have a list of arbitrary length, and I need to split it up into equal size chunks and operate on it. There are some obvious ways to do this, like keeping a counter and two lists, and when the second list fills up, add it to the first list and empty the second list for the next round of data, but thi...
What is JavaScript garbage collection?
What is JavaScript garbage collection? What's important for a web programmer to understand about JavaScript garbage collection, in order to write better code?
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Error to install Nokogiri on OSX 10.9 Maverick?
I upgraded my OSX (Lion) to Mavericks and I can't install Nokogiri for my projects.
30 Answers
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How do I pass a unique_ptr argument to a constructor or a function?
I'm new to move semantics in C++11 and I don't know very well how to handle unique_ptr parameters in constructors or functions. Consider this class referencing itself:
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Python hashable dicts
As an exercise, and mostly for my own amusement, I'm implementing a backtracking packrat parser. The inspiration for this is i'd like to have a better idea about how hygenic macros would work in an algol-like language (as apposed to the syntax free lisp dialects you normally find them in). Because...
How can I restart a Java application?
How can I restart a Java AWT application? I have a button to which I have attached an event handler. What code should I use to restart the application?
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Is there a good reason to use upper case for SQL keywords? [closed]
The default seems to be upper case, but is there really any reason to use upper case for keywords? I started using upper case because I was just trying to match what SQL Server gives me whenever I tried to create something, like a new stored procedure. But then, I felt terrible for my baby (5th) fin...
What is the difference between map and flatMap and a good use case for each?
Can someone explain to me the difference between map and flatMap and what is a good use case for each?
16 Answers
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