joining on the paginator

Posts: 3 · Posted: Mon Aug 28, 2006 11:11 pm

Hi!

I can't seem to guess how I should specify the join between these two tables, to have the category name added to the output.
The tables are

Code:

create_table "message_categories", :force => true do |t|
t.column "name", :string, :null => false
end

create_table "messages", :force => true do |t|
t.column "message_category_id", :integer, :default => 0, :null => false
t.column "name", :string, :null => false
t.column "sort", :integer, :null => false
end

the code I tried to add is

Code:

def component
@show_wrapper = true if @show_wrapper.nil?
@sort_sql = Message.scaffold_columns_hash[current_sort(params)].sort_sql rescue nil
@sort_by = @sort_sql.nil? ? "#{Message.table_name}.#{Message.primary_key} asc" : @sort_sql + " " + current_sort_direction(params)
@paginator, @messages = paginate :messages, :per_page => 40, :order => 'sort DESC, name', :joins => "#{MessageCategory.name}"

render :action => "component", :layout => false
end

In particular, I added :joins => "#{MessageCategory.name}", but I cannot find any example and I'm definitely doubtful about the syntax. Last but not least, I'm using ajax_scaffold, which is one of the greatest things I ever saw (and in 28 years of work I saw a lot of them). Very Happy

Any hint is extremely welcome.

Posts: 3 · Posted: Tue Aug 29, 2006 2:52 pm

okay I found a first answer, at least formally all I need is plain SQL

Code:

@paginator, @messages = paginate :messages, :per_page => 30, :conditions => "m.message_category_id=mc.id", :joins => "m, message_categories mc", :select => "m.*, mc.name AS category_name", :order => 'mc.name, m.sort, m.name'

Too bad I don't see the category name in the view Evil or Very Mad

So acting on the paginator was NOT the answer, after all... any hint?

Posts: 3 · Posted: Tue Aug 29, 2006 3:43 pm

LOL it was born as a question, it evolved into a blog Very Happy

The answer for all such questions is here http://height1percent.com/articles/2006/04/18/ajaxscaffold-3-1-0-released

The more I see Ruby, the more I love it... I just wish it had a central doc repository in the friendly, commented PHP style. It would save us all a lot of trouble.