Ferret talk - Jul 2006 - Search on data accross many tables, linked by belongs_to

I am using Ferret and acts_as_ferret, as my search back-end for my Rails 
project. I have a question about using acts_as_ferret on a main table 
that is linked to other tables by foreign keys. Is there a way to 
include the information linked by the belongs_to keyword in the search 
results ?

As an example, let''s say I have a main table ''posts'':

============================|  posts
============================   id
   title
   content
   category_id

where category_id is a foreign key pointing to a row of the table 
''categories'':

============================|  categories
============================   id
   name

My Rails models are then:

class Post < ActiveRecord::Base
    belongs_to :category
    acts_as_ferret :fields => [ ''title'',
''content'' ]
end

class Category < ActiveRecord::Base
     has_many :posts
end


I would want to be able to change the following line
         acts_as_ferret :fields => [ ''title'',
''content'' ]
to
         acts_as_ferret :fields => [ ''title'',
''content'', ''category.name''
]

and have Ferret search for records specified by title, content and 
category name.

Is there an known solution to my problem ? In Ferret, how can I specify 
a search accross many tables for results returning only a main class (in 
the example, search all posts that have a certain category name by just 
typing that cateogry name as the query) ? Do I have to create a new 
model class PostIndex that gathers all the information just for the 
indexing, even though the information is not stored that way in the 
database ?

Thanks a lot for your help,
Maxime Curioni

-- 
Posted via http://www.ruby-forum.com/.

Hi Maxime,

On Sat, Jul 08, 2006 at 12:13:53AM +0200, Maxime Curioni
wrote:
> I am using Ferret and acts_as_ferret, as my search back-end for my Rails 
> project. I have a question about using acts_as_ferret on a main table 
> that is linked to other tables by foreign keys. Is there a way to 
> include the information linked by the belongs_to keyword in the search 
> results ?
> 
[..]
> My Rails models are then:
> 
> class Post < ActiveRecord::Base
>     belongs_to :category
>     acts_as_ferret :fields => [ ''title'',
''content'' ]
> end
> 
> class Category < ActiveRecord::Base
>      has_many :posts
> end
> 
> 
> I would want to be able to change the following line
>          acts_as_ferret :fields => [ ''title'',
''content'' ]
> to
>          acts_as_ferret :fields => [ ''title'',
''content'', ''category.name''
> ]
> 
> and have Ferret search for records specified by title, content and 
> category name.
you could use 

acts_as_ferret :fields => [ ''title'',
''content'', :category_name]
def category_name
  category.name
end

to achieve this.

Jens

-- 
webit! Gesellschaft f?r neue Medien mbH          www.webit.de
Dipl.-Wirtschaftsingenieur Jens Kr?mer       kraemer at webit.de
Schnorrstra?e 76                         Tel +49 351 46766  0
D-01069 Dresden                          Fax +49 351 46766 66

Thanks Jens, I didn''t know it was that simple !

> you could use
> 
> acts_as_ferret :fields => [ ''title'',
''content'', :category_name]
> def category_name
>   category.name
> end
> 
> to achieve this.
> 
> Jens

-- 
Posted via http://www.ruby-forum.com/.

Hmm. I tried doing it with a few levels of nesting like:

acts_as_ferret :fields => { :menu_item_name, ''city'',
''state'', ''zip'' }

def menu_item_name
 menus.menu_categories.menu_items.name
end

And I don''t get any results.

The tables in the DB are like:

menus

menu_categories
menu_id

menu_items
menu_category_id

Am I missing something???



Maxime Curioni wrote:
> Thanks Jens, I didn''t know it was that simple !
> 
> 
>> you could use
>> 
>> acts_as_ferret :fields => [ ''title'',
''content'', :category_name]
>> def category_name
>>   category.name
>> end
>> 
>> to achieve this.
>> 
>> Jens

-- 
Posted via http://www.ruby-forum.com/.

On Thu, Jul 13, 2006 at 04:59:02PM +0200, Guest wrote:
> 
> Hmm. I tried doing it with a few levels of nesting like:
> 
> acts_as_ferret :fields => { :menu_item_name, ''city'',
''state'', ''zip'' }
> 
> def menu_item_name
>  menus.menu_categories.menu_items.name
> end
> 
> And I don''t get any results.
that can have many reasons ;-)
Basically, what you do in the method is irrelevant to ferret, it just
indexes what is returned by the method.

You should see what fields acts_as_ferret adds to the index 
in your development log when you save a record. 
please check there if it adds what you want.

Jens

-- 
webit! Gesellschaft f?r neue Medien mbH          www.webit.de
Dipl.-Wirtschaftsingenieur Jens Kr?mer       kraemer at webit.de
Schnorrstra?e 76                         Tel +49 351 46766  0
D-01069 Dresden                          Fax +49 351 46766 66

OK, when I create the top level item, it indexes the fields, but since 
I''m creating the menus and menu_items separately it doesn''t
look like
those are getting indexed according to the log. Do I have to set 
something else up?

Thanks Jens!

Jens Kraemer wrote:
> On Thu, Jul 13, 2006 at 04:59:02PM +0200, Guest wrote:
>> 
>> Hmm. I tried doing it with a few levels of nesting like:
>> 
>> acts_as_ferret :fields => { :menu_item_name,
''city'', ''state'', ''zip'' }
>> 
>> def menu_item_name
>>  menus.menu_categories.menu_items.name
>> end
>> 
>> And I don''t get any results.
> 
> that can have many reasons ;-)
> Basically, what you do in the method is irrelevant to ferret, it just
> indexes what is returned by the method.
> 
> You should see what fields acts_as_ferret adds to the index
> in your development log when you save a record.
> please check there if it adds what you want.
> 
> Jens
> 
> --
> webit! Gesellschaft f?r neue Medien mbH          www.webit.de
> Dipl.-Wirtschaftsingenieur Jens Kr?mer       kraemer at webit.de
> Schnorrstra?e 76                         Tel +49 351 46766  0
> D-01069 Dresden                          Fax +49 351 46766 66

-- 
Posted via http://www.ruby-forum.com/.

Wait so, now I added acts_as_ferret in the menu_item model, and it looks 
as it''s it''s being indexed in the log, but I still
don''t get the
results.

Hmm...

Guest wrote:
> 
> 
> OK, when I create the top level item, it indexes the fields, but since 
> I''m creating the menus and menu_items separately it
doesn''t look like
> those are getting indexed according to the log. Do I have to set 
> something else up?
> 
> Thanks Jens!
> 
> Jens Kraemer wrote:
>> On Thu, Jul 13, 2006 at 04:59:02PM +0200, Guest wrote:
>>> 
>>> Hmm. I tried doing it with a few levels of nesting like:
>>> 
>>> acts_as_ferret :fields => { :menu_item_name,
''city'', ''state'', ''zip'' }
>>> 
>>> def menu_item_name
>>>  menus.menu_categories.menu_items.name
>>> end
>>> 
>>> And I don''t get any results.
>> 
>> that can have many reasons ;-)
>> Basically, what you do in the method is irrelevant to ferret, it just
>> indexes what is returned by the method.
>> 
>> You should see what fields acts_as_ferret adds to the index
>> in your development log when you save a record.
>> please check there if it adds what you want.
>> 
>> Jens
>> 
>> --
>> webit! Gesellschaft f?r neue Medien mbH          www.webit.de
>> Dipl.-Wirtschaftsingenieur Jens Kr?mer       kraemer at webit.de
>> Schnorrstra?e 76                         Tel +49 351 46766  0
>> D-01069 Dresden                          Fax +49 351 46766 66

-- 
Posted via http://www.ruby-forum.com/.

Hi!

On Thu, Jul 13, 2006 at 07:53:36PM +0200, Guest wrote:
> 
> Wait so, now I added acts_as_ferret in the menu_item model, and it looks 
> as it''s it''s being indexed in the log, but I still
don''t get the
> results.
calling acts_as_ferret in the MenuItem class will create a separate
index for MenuItems, this is probably not what you want.

The problem is, that ferret only can index what your menu_item_name 
method delivers when the object is saved. If you save the object before
creating the menus and menu_items, there''s nothing to index.

You could try to create the menus and menu_items first, then add them to
the object to be indexed and then call save. 

Or just call save another time after you created the menus.

btw, ''menuitems'' sounds like it is a collection of menuitems,
so what
should ''menuitems.name'' deliver ? Maybe you want something
like

menuitems.inject('''') { |value, item| value << "
#{item.name}" }

concatenating the names of all menuitems to one string which then would
be indexed ? The same for ''menus'', sounds like a has_many
relationship, too.


I''m sure we''ll get this right somehow ;-)

Jens
> Hmm...
> 
> Guest wrote:
> > 
> > 
> > OK, when I create the top level item, it indexes the fields, but since
> > I''m creating the menus and menu_items separately it
doesn''t look like
> > those are getting indexed according to the log. Do I have to set 
> > something else up?
> > 
> > Thanks Jens!
> > 
> > Jens Kraemer wrote:
> >> On Thu, Jul 13, 2006 at 04:59:02PM +0200, Guest wrote:
> >>> 
> >>> Hmm. I tried doing it with a few levels of nesting like:
> >>> 
> >>> acts_as_ferret :fields => { :menu_item_name,
''city'', ''state'', ''zip'' }
> >>> 
> >>> def menu_item_name
> >>>  menus.menu_categories.menu_items.name
> >>> end
> >>> 
> >>> And I don''t get any results.
> >> 
> >> that can have many reasons ;-)
> >> Basically, what you do in the method is irrelevant to ferret, it
just
> >> indexes what is returned by the method.
> >> 
> >> You should see what fields acts_as_ferret adds to the index
> >> in your development log when you save a record.
> >> please check there if it adds what you want.
> >> 
> >> Jens
> >> 
> >> --
> >> webit! Gesellschaft f?r neue Medien mbH          www.webit.de
> >> Dipl.-Wirtschaftsingenieur Jens Kr?mer       kraemer at webit.de
> >> Schnorrstra?e 76                         Tel +49 351 46766  0
> >> D-01069 Dresden                          Fax +49 351 46766 66
> 
> 
> -- 
> Posted via http://www.ruby-forum.com/.
> _______________________________________________
> Ferret-talk mailing list
> Ferret-talk at rubyforge.org
> http://rubyforge.org/mailman/listinfo/ferret-talk
-- 
webit! Gesellschaft f?r neue Medien mbH          www.webit.de
Dipl.-Wirtschaftsingenieur Jens Kr?mer       kraemer at webit.de
Schnorrstra?e 76                         Tel +49 351 46766  0
D-01069 Dresden                          Fax +49 351 46766 66

Should this be able to work from the Console?  For example, let''s
assume
there is a Post record with a Category name of "Help"...

Post.find_by_contents("Help")

For some reason this does not generate any results...

Maxime Curioni wrote:
> Thanks Jens, I didn''t know it was that simple !
> 
> 
>> you could use
>> 
>> acts_as_ferret :fields => [ ''title'',
''content'', :category_name]
>> def category_name
>>   category.name
>> end
>> 
>> to achieve this.
>> 
>> Jens

-- 
Posted via http://www.ruby-forum.com/.

On Tue, Nov 28, 2006 at 01:36:43AM +0100, John Perkins
wrote:
> Should this be able to work from the Console?  For example, let''s
assume
> there is a Post record with a Category name of "Help"...
> 
> Post.find_by_contents("Help")
> 
> For some reason this does not generate any results...
it should work from the console. what if you do Post.rebuild_index
before the find_by_contents call ?

Jens

-- 
webit! Gesellschaft f?r neue Medien mbH          www.webit.de
Dipl.-Wirtschaftsingenieur Jens Kr?mer       kraemer at webit.de
Schnorrstra?e 76                         Tel +49 351 46766  0
D-01069 Dresden                          Fax +49 351 46766 66