Looping through results of complex query

Rails
1

Hello,
I have a postgresql join query that returns all the correct values on
command line but when I try to loop through the results in a view, I
can’t
access all the fields.

Specifically, I’m trying to display the fields in the rations table and
can’t seem to print them out to save my life.

Here’s the query:

@herd_rations_during_season = HerdRation.find(:all,
        :joins => ["INNER JOIN seasons ON seasons.herd_id =
herd_rations.herd_id AND seasons.season_start_date >=
herd_rations.grazing_begun AND herd_rations.grazing_end <=
seasons.season_end_date INNER JOIN rations ON rations.id =
herd_rations.ration_id"],
          :select=>'DISTINCT ON (herd_rations.id) herd_rations.id,
herd_rations.grazing_begun, herd_rations.grazing_end, 
seasons.season_name,
seasons.season_start_date, seasons.season_end_date, 
rations.ration_name',
          :conditions => ["herd_rations.herd_id=?", params[:id]])

@herd_rations_during_season.each do |herd_ration|
  puts("----herd_ration: #{herd_ration.ration}")           #prints nil
  puts("----grazing_begun: #{herd_ration.grazing_begun}")  #good
  puts("---- grazing_end: #{herd_ration.grazing_end}")    #good
end

Thanks for any help!

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2

Probably because in your select clause, you aren’t selecting
herd_rations.ration

3

solved the problem and feel a bit stupid but, at the same time not.

I accessed ration.ration_name by simply doing this in my loop:

herd_ration.ration_name

The part I’m not understanding, is that when I used inspect in the loop,
it
did not display any reference to to ration.ration_name:

@herd_rations_during_season.each do |herd_ration|
  puts("----herd_ration: #{herd_ration.inspect}")   #doesn't display
ration_name anywhere
end

Chirag S. wrote:

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4

On Jul 9, 5:41pm, clem_c_rock [email protected] wrote:

solved the problem and feel a bit stupid but, at the same time not.

I accessed ration.ration_name by simply doing this in my loop:

herd_ration.ration_name

The part I’m not understanding, is that when I used inspect in the loop, it
did not display any reference to to ration.ration_name:

inspect by design only shows columns from the model’s table, no matter
what other stuff you may have put in the select clause

Fred

5

appreciate your reply Fred - you are always a great help!

Frederick C.-2 wrote:

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[code]

https://groups.google.com/d/msg/rubyonrails-talk/-/xlhlA_zkL10J.

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6

For anyone that’s interested … You can inspect the model’s
current attributes to see that additional data that was added in your
custom query:

…
puts("----herd_ration: #{herd_ration.attributes.inspect}")
…

Jeff