Rails - Feb 2006 - self in before_create

Hi, I am having a small problem concernig how to access local variables in
before_create. I am not sure how to really form this question but here goes:

I am wondering why this works

  def before_create
    self.last_logged_in = Time.now
    self.created = Time.now
  end

but this doesn''t

  def before_create
    @last_logged_in = Time.now
    @created = Time.now
  end

The latter fails with the following error:

Mysql::Error: #23000Column ''last_logged_in'' cannot be null:

On Tue, Feb 14, 2006 at 06:29:16PM +0000, Bjarki Gudlaugsson
wrote:
> Hi, I am having a small problem concernig how to access local variables in
> before_create. I am not sure how to really form this question but here
goes:
> 
> I am wondering why this works
> 
>   def before_create
>     self.last_logged_in = Time.now
>     self.created = Time.now
>   end
> 
> but this doesn''t
> 
>   def before_create
>     @last_logged_in = Time.now
>     @created = Time.now
>   end
I don''t think this is a before_create-specific problem.  In general,
the
database fields in an AR object aren''t just instance variables --
they''re
actually values in the @attributes (from memory) instance variable.  So
you''d need to do

def before_create
  @attributes[''last_logged_in''] = Time.now
  @attributes[''created''] = Time.now
end

But, of course, that''s a damn sight longer than self.<whatever>,
so stick
with that.

On another optimisation point, if you create a field in your database called
''created_at'', AR will automatically fill that field out with
Time.now at
object creation time, which will save you a couple of lines of code here and
there.

- Matt