# Automatic loading of parent association weirdness?

**URL:** <https://www.ruby-forum.com/t/automatic-loading-of-parent-association-weirdness/150544>\
**Category:** Rails\
**Created:** [October 9, 2008, 6:44pm UTC](https://www.ruby-forum.com/t/automatic-loading-of-parent-association-weirdness/150544 "2008-10-09T18:44:00Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![xavier](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/x/2bfe46/32.png) [@xavier](https://www.ruby-forum.com/u/xavier)\
**Post date:** [October 9, 2008, 6:44pm UTC](https://www.ruby-forum.com/t/automatic-loading-of-parent-association-weirdness/150544/1 "2008-10-09T18:44:00Z")

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Hi there,

I’m experiencing some weird behavior with automatic loading of parent  
associations in ActiveRecord using Rails 2.1.

Let’s take this simple model:

class Contact \< ActiveRecord::Base  
has\_many :assets  
end

class Asset \< ActiveRecord::Base  
belongs\_to :contact  
end

And here follows a console/development.log transcript:

> > a = Asset.find(:first, :include =\> {:contact =\> :assets})

Asset Load (0.000399) SELECT \* FROM `assets` LIMIT 1  
Contact Load (0.000300) SELECT \* FROM `contacts` WHERE  
(`contacts`.id IN (‘1’))  
Asset Load (0.009318) SELECT `assets`.\* FROM `assets` WHERE  
(`assets`.contact\_id IN (1))

(looks alright to me)

> > c = a.contact

(This yields no query, as expected)

> > f = c.assets.first

(This yields no query, as expected)

> > f.contact

Contact Load (0.000408) SELECT \* FROM `contacts` WHERE  
(`contacts`.`id` = 1)

Now why isn’t this asset’s contact record already associated to the  
existing contact instance?

I’ve been using Rails for years and it’s the very first time I notice  
such a behavior. It has always occured to me that, when invoking  
parent.association, all records in association had their parent  
already set to an existing instance, without having to hit the  
database.

Any idea on this?

Greets,

Xavier

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<div class="post-metadata">

**Author:** ![xavier](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/x/2bfe46/32.png) [@xavier](https://www.ruby-forum.com/u/xavier)\
**Post date:** [October 9, 2008, 6:47pm UTC](https://www.ruby-forum.com/t/automatic-loading-of-parent-association-weirdness/150544/2 "2008-10-09T18:47:32Z")

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On 9 Oct 2008, at 17:36, Xavier wrote:

> parent.association, all records in association had their parent  
> already set to an existing instance, without having to hit the  
> database.

It’s always been like this (:include is a red herring here, even  
without eager loading in the picture, if you do

x = parent.child #=\> 1 query, loads child  
x.parent #=\> 1 query, loads parent again)

This is far from ideal but it’s nothing new

Fred

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<div class="post-metadata">

**Author:** ![xavier](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/x/2bfe46/32.png) [@xavier](https://www.ruby-forum.com/u/xavier)\
**Post date:** [October 10, 2008, 11:39am UTC](https://www.ruby-forum.com/t/automatic-loading-of-parent-association-weirdness/150544/3 "2008-10-10T11:39:10Z")

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> This is far from ideal but it’s nothing new

Wow, I am so totally baffled.

I’m still wondering how I managed to never notice this, I’ve always  
taken the presence of the parent for granted when loading members of  
an association… probably because this lack doesn’t make a whole lot  
of sense, does it? 😉

Thanks for the reality check anyway.

Cheers

Xavier