Rails - Jun 2010 - How to find models that have at least one associated has_many

I''m having a senior moment.  I''ve done this before but I
can''t remember how.

Two active record models,

Foo belongs_to Bar

Bar has_many Foos

I want to find all Bars that have at least one Foo, is it:

Bar.all(:include => :foos, :conditions => "foo.id IS NOT
NULL'')

or something else?

-- 
Rick DeNatale

Blog: http://talklikeaduck.denhaven2.com/
Github: http://github.com/rubyredrick
Twitter: @RickDeNatale
WWR: http://www.workingwithrails.com/person/9021-rick-denatale
LinkedIn: http://www.linkedin.com/in/rickdenatale

-- 
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en.

Hi Rick,

On Fri, Jun 11, 2010 at 1:26 PM, Rick DeNatale
<rick.denatale-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> I''m having a senior moment.  I''ve done this before but I
can''t remember how.
>
> Two active record models,
>
> Foo belongs_to Bar
>
> Bar has_many Foos
>
> I want to find all Bars that have at least one Foo, is it:
>
> Bar.all(:include => :foos, :conditions => "foo.id IS NOT
NULL'')
Seems like it would be ''foo.bar_id'' in the condition clause.

HTH,
Bill

-- 
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en.

On 11 June 2010 19:26, Rick DeNatale
<rick.denatale-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
> I''m having a senior moment.  I''ve done this before but I
can''t remember how.
>
> I want to find all Bars that have at least one Foo, is it:
>
> Bar.all(:include => :foos, :conditions => "foo.id IS NOT
NULL'')
>
> or something else?
Doesn''t...

  Bar.all(:joins => :foos).uniq

...do the job?

-- 
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en.

On 11 June 2010 20:10, Michael Pavling
<pavling-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:
>  Bar.all(:joins => :foos).uniq
Seems to... quick and dirty test on one of my models:
>> Person.all(:include => :graduations).select { |person|
!person.graduations.empty? }.size
=> 87
>> Person.all(:include => :graduations).select { |person|
person.graduations.size > 0 }.size
=> 87
>> Person.all(:joins => :graduations).size
=> 103
>> Person.all(:joins => :graduations).uniq.size
=> 87
>>
-- 
You received this message because you are subscribed to the Google Groups
"Ruby on Rails: Talk" group.
To post to this group, send email to
rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org
To unsubscribe from this group, send email to
rubyonrails-talk+unsubscribe@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/rubyonrails-talk?hl=en.