How to use ActiveRecord to retrieve all columns and rows... ?

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June 25th, 2008, 10:20 PM

r2b2

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How to use ActiveRecord to retrieve all columns and rows... ?

Hi, how can i use ActiveRecord associations to retrieve all columns and rows including the columns and rows in the referenced table.

for example :

Code:

* = primary key
+ = foreign key

Table : parents
*id 
parent_name

Table : kids
*id
+parent_id
kid_name

class Parent < ActiveRecord::Base
   has_many :kids
end

class Kid < ActiveRecord::Base
   belongs_to :parents
end

How can I get all the columns present in this two table and produce something like:

Code:

parents.id, parents.parent_name, kids.id, kids.parent_id, kids.kid_name

I only assume that the above ActiveRecord associations executes something like :

Code:

SELECT parents.id, parents.parent_name, kids.id, kids.parent_id, kids.kid_name
FROM parents left join kids on parents.id = kids.parent_id

Thanks

June 26th, 2008, 02:43 PM

Scorpions4ever

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Something like this:

Code:

@array = []
parents = Parent.find(:all)
parents.each do |p|
   kids = p.kids
   kids.each do |k|
      # Do something with the data
      str = "#{p.id} #{p.parent_name} #{k.id} #{k.parent_id}"
      @array << str
   end
end

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