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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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How to generate random number in Bash?
...le this is fine in a pinch, doing arithmetic on random numbers can dramatically affect the randomness of your result. in the case of $RANDOM % 10, 8 and 9 are measurably (though marginally) less probable than 0-7, even if $RANDOM is a robust source of random data.
– dimo414
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how to read all files inside particular folder
I want to read all xml files inside a particular folder in c# .net
7 Answers
7
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Creating a div element in jQuery [duplicate]
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@Ricki - no, use double-quotes for all attributes. Single quotes do not produce valid XHTML, although most browsers will tolerate it.
– halfer
Oct 22 '11 at 12:21
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How can I develop for iPhone using a Windows development machine?
...the old Dell Precision I had at the time :)
There are three routes;
Install OSx86 (aka iATKOS / Kalyway) on a second partition/disk and dual boot.
Run Mac OS X Server under VMWare (Mac OS X 10.7 (Lion) onwards, read the update below).
Use Delphi XE4 and the macincloud service. This is a commercia...
Disable Laravel's Eloquent timestamps
...this moment we don't want to add the updated_at / created_at fields to all of our tables as we have a logging class that does all this in more depth for us already.
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Getting Git to work with a proxy server - fails with “Request timed out”
...thout proxy:
Command to use:
git config --global --unset http.proxy
Finally, to check the currently set proxy:
git config --global --get http.proxy
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MongoDB vs. Cassandra [closed]
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Totally different, a comment isn't big enough, but ... Cassandra is a linearly scalable (amortized constant time reads & writes) dynamo/google bigtable hybrid that features fast writes regardless of data size. It's feature s...
Is there any way to enforce typing on NSArray, NSMutableArray, etc.?
Can I make a NSMutableArray instance where all the elements are of type SomeClass ?
11 Answers
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Declaring an unsigned int in Java
... however, are different. As of Java SE 8, new methods in the Integer class allow you to fully use the int data type to perform unsigned arithmetic:
In Java SE 8 and later, you can use the int data type to represent an unsigned 32-bit integer, which has a minimum value of 0 and a maximum value of...