Rails - Aug 2006 - how do set default value for ActiveRecord fields?

Everytime a new record object is created i.e. Record.new, i want certain 
fields to be the same.

Any idea how to do this?
Thanks
Chris

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On Aug 01, 2006, at 12:26 pm, Chris wrote:
> Everytime a new record object is created i.e. Record.new, i want  
> certain
> fields to be the same.
>
> Any idea how to do this?
> Thanks
> Chris
Chris,

You want to set defaults in the database columns.  The easiest way to  
do this is to build your database with Rails migrations: http:// 
wiki.rubyonrails.org/rails/pages/UnderstandingMigrations and  
use :default => XXX in your column definitions.

Ashley

On Tuesday, August 01, 2006, at 1:26 PM, Chris wrote:
>Everytime a new record object is created i.e. Record.new, i want certain
>fields to be the same.
>
>Any idea how to do this?
>Thanks
>Chris
>
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>Posted via http://www.ruby-forum.com/.
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>Rails mailing list
>Rails@lists.rubyonrails.org
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Easiest way would be to define :default=>some_value in the migration for  
each column

t.column "title", :string, :default=>''test''

_Kevin
www.sciwerks.com

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So when you create a new activerecord instance (before you save it) does 
it look to see what the default value is from the schema?

I want the default value to be assigned upon creation of the object, 
i.e. Record.new, and not when it gets saved.

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Chris wrote:
> So when you create a new activerecord instance (before you save it) does 
> it look to see what the default value is from the schema?
> 
> I want the default value to be assigned upon creation of the object, 
> i.e. Record.new, and not when it gets saved.
Set the default value in the controller.

eg.
def firstpage
  Tablename.column = default_value
end

I havn''t looked at ruby for a while but its something like that.
Does this help?

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On 2006-08-01, at 10:02 , Simon wrote:
> Chris wrote:
>> So when you create a new activerecord instance (before you save  
>> it) does
>> it look to see what the default value is from the schema?
>>
It does. That''s also why you can''t have expressions as
defaults (eg.
NOW()), just literals.
>> I want the default value to be assigned upon creation of the object,
>> i.e. Record.new, and not when it gets saved.
Yep. Rails will look it up, it''ll be set at instantiation.
> Set the default value in the controller.
Bad idea. Let the model handle it.

I''m thinking about writing a plugin that initializes default values.  
It''s useful when you have more complex defaults, e.g. with  
inheritance, that each descendant model may have a different default  
for the same field. Sintax would be something like

   class Post < AR...
     defaults :title => ''(untitled)'', :status =>
''unpublished'',
       :whatever => lambda { |record| ... some dynamic magic ... }
   end

You can also do similar just by overriding the accessors.