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Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...
Python decorators in classes
... Michael SpeerMichael Speer
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7
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How to print the contents of RDD?
...save in a single file, you can coalesce you RDD into one partition before calling saveAsTextFile, but again this may cause issues. I think the best option is to write in multiple files in HDFS, then use hdfs dfs --getmerge in order to merge the files
– Oussama
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How to print out the method name and line number and conditionally disable NSLog?
...d with a semicolon?
– Monstieur
Apr 16 '15 at 6:43
@Locutus So you don't have to put a semicolon after the DLog statem...
ASP.NET MVC Razor pass model to layout
...have modeled your viewmodels a bit wrong if you have this problem.
Personally I would never type a layout page. But if you want to do that you should have a base viewmodel that your other viewmodels inherits from and type your layout to the base viewmodel and you pages to the specific once.
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How to clear the cache in NetBeans
... me absolutely crazy, trying to track down bugs for hours that weren't actually there -- the class with the main method was not being found, and some custom exception classes were not being recognized as implementing Throwable... I just deleted the stupid cache, and now all of it works fine.
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Ensure that HttpConfiguration.EnsureInitialized()
I've installed Visual Studio 2013 and when I run my app I get the error below.
14 Answers
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What are C++ functors and their uses?
...42); // create an instance of the functor class
int i = add42(8); // and "call" it
assert(i == 50); // and it added 42 to its argument
std::vector<int> in; // assume this contains a bunch of values)
std::vector<int> out(in.size());
// Pass a functor to std::transform, which calls the fu...
Simple C example of doing an HTTP POST and consuming the response
...esponse without the use of curl (the libraries are not and will not be installed on the machine this needs to run).
4 Answe...
Why do assignment statements return a value?
This is allowed:
14 Answers
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