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Correct way to use get_or_create?
...f the fields have to be included in defaults. In case CREATE event occurs, all the fields are taken into consideration.
It looks like you need to be returning into a tuple, instead of a single variable, do like this:
customer.source,created = Source.objects.get_or_create(name="Website")
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is not JSON serializable
...fe tage. stackoverflow.com/a/57939897/4157431
– Rami Alloush
Sep 14 '19 at 23:01
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what are the .map files used for in Bootstrap 3.x?
There are two files included in the CSS folder with .map file extensions. They are:
8 Answers
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How do I cast a variable in Scala?
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The preferred technique is to use pattern matching. This allows you to gracefully handle the case that the value in question is not of the given type:
g match {
case g2: Graphics2D => g2
case _ => throw new ClassCastException
}
This block replicates the semantics of th...
Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
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add_column :status, :string, :default => "P"
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OR
You can use a callback, before_save
class Task < ActiveRecord::Base
before_save :default_values
def default_values
self.status ||= 'P' # note self.status = 'P' if self.status.nil? might be safer (per @frontendbeauty)
end
end
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Good tool to visualise database schema? [closed]
...om). It works with a variety of databases including SQLite, and their EULA allows the free version to be used for commercial projects.
– Aralox
Jul 29 '16 at 5:05
add a commen...
What is a word boundary in regex?
... be "identifier" characters (alnums and underscore), not as anything especially useful for English.
– hobbs
Aug 24 '09 at 21:02
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How to jump to a particular line in a huge text file?
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linecache:
The linecache module allows one to get any line from a Python source file, while attempting to optimize internally, using a cache, the common case where many lines are read from a single file. This is used by the traceback module to retrieve sour...
Is there an opposite of include? for Ruby Arrays?
... Minor remark: AS adds it to Enumerable so you can use it with all classes which include Enumerable. Even with Hash. :)
– user2422869
Aug 5 '15 at 5:04
1
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JAX-RS / Jersey how to customize error handling?
...o wrap an existing Exception, perhaps an ObjectNotFoundException with an small wrapper class that implements the ExceptionMapper interface annotated with a @Provider annotation. This tells the JAX-RS runtime, that if the wrapped Exception is raised, return the response code defined in the Exception...