# help with :include on active record finds **URL:** \ **Category:** rubyonrails-talk\ **Created:** [June 6, 2008, 9:15pm UTC](https://discuss.rubyonrails.org/t/help-with-include-on-active-record-finds/30338 "2008-06-06T21:15:42Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Sean\_O\_Hara](https://avatars.discourse-cdn.com/v4/letter/s/2bfe46/32.png) [@Sean\_O\_Hara](https://discuss.rubyonrails.org/u/Sean_O_Hara)\ **Post date:** [June 6, 2008, 9:15pm UTC](https://discuss.rubyonrails.org/t/help-with-include-on-active-record-finds/30338/1 "2008-06-06T21:15:42Z")
Hi All, I am having trouble getting the :include option to work on my active record finds. They are not eager loading, adding the joins to the sql queries. Has anyone had this problem? Here is my query: @cart = Cart.find\_by\_id(session[:cart\_id], :include =\> [:cart\_items]) This is generating the following query: SELECT \* FROM `carts` WHERE (`carts`.`id` = 23) LIMIT 1 Rails is not eager loading the cart\_items which belongs\_to cart. Does anyone know why? Thanks, Sean ---
**Author:** ![Philip\_Hallstrom](https://avatars.discourse-cdn.com/v4/letter/p/bbe5ce/32.png) [@Philip\_Hallstrom](https://discuss.rubyonrails.org/u/Philip_Hallstrom)\ **Post date:** [June 6, 2008, 9:20pm UTC](https://discuss.rubyonrails.org/t/help-with-include-on-active-record-finds/30338/2 "2008-06-06T21:20:26Z")
> Hi All, I am having trouble getting the :include option to work on my active record finds. They are not eager loading, adding the joins to the sql queries. Has anyone had this problem? Here is my query: > >    @cart = Cart.find\_by\_id(session[:cart\_id], :include =\> [:cart\_items]) > > This is generating the following query: SELECT \* FROM `carts` WHERE (`carts`.`id` = 23) LIMIT 1 > > Rails is not eager loading the cart\_items which belongs\_to cart. Does anyone know why? Don't think it can. Not in a single query. You have one cart that has many items. You can't return all of that in a single query unless you want to send duplicate rows for the cart for every row of the cart item. There may be right after that line in the logs a line fetching the cart items. Or Rails might not do it since it's not possible. If I'm thinking clearly that is 🙂 ---
**Author:** ![Pardee\_Roy](https://avatars.discourse-cdn.com/v4/letter/p/f0a364/32.png) [@Pardee\_Roy](https://discuss.rubyonrails.org/u/Pardee_Roy)\ **Post date:** [June 6, 2008, 10:16pm UTC](https://discuss.rubyonrails.org/t/help-with-include-on-active-record-finds/30338/3 "2008-06-06T22:16:52Z")
Nah, that should work I think--see the "Eager Loading" section on [http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethod](http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethod) s.html I just tried this out in a toy app of my own, and was surprised to see in my log that \*in addition\* to the left-join query immediately under the heading "Processing OrganizationsController#show", there were 3 other queries that followed the heading "Rendering organizations/show". One was triggered by (I think) this line in my view:   \<% if @organization.people.count \> 0 %\> That generated a:   SELECT count(\*) AS count\_all FROM `people` WHERE (people.organization\_id = 1) Then I have 2 instances of:   SELECT \* FROM `organizations` WHERE (`organizations`.`id` = 1) Which I believe are caused by resolving the person.organization.name calls in the part of the view that lists the people belonging to @organization. So... not that this isn't a bit dismaying, BUT--is there any chance that you too are looking at calls generated not by your find\_by\_id call, but by subsequent view activity? Cheers, -Roy ---
**Author:** ![Sean\_O\_Hara](https://avatars.discourse-cdn.com/v4/letter/s/2bfe46/32.png) [@Sean\_O\_Hara](https://discuss.rubyonrails.org/u/Sean_O_Hara)\ **Post date:** [June 6, 2008, 10:27pm UTC](https://discuss.rubyonrails.org/t/help-with-include-on-active-record-finds/30338/4 "2008-06-06T22:27:21Z")
I don’t think it has to do with view activity, because the cart and cart\_items queries are generated by a before\_filter… and the are only run once. Plus, they are instantiating the @cart and it’s .cart\_items children, so I don’t think any view methods would affect that. Maybe in your case you can call @organization.people.size to avoid the sql. There are other finds in my site that aren’t generating the eager loading queries like I would expect (and I believe rails used to, prior to rails 2.0.2). Here’s the kind of query I would expect rails to generated based on the find statement: ---
**Author:** ![Frederick\_Cheung](https://sea2.discourse-cdn.com/rubyonrails/user_avatar/discuss.rubyonrails.org/frederick_cheung/32/3901_2.png) [@Frederick\_Cheung](https://discuss.rubyonrails.org/u/Frederick_Cheung)\ **Post date:** [June 6, 2008, 10:33pm UTC](https://discuss.rubyonrails.org/t/help-with-include-on-active-record-finds/30338/5 "2008-06-06T22:33:39Z")
Eager loading in rails 2.1 changed: [Mixing :include and :conditions - Space Vatican](http://www.spacevatican.org/2008/4/29/include-and-conditions) Fred ---
**Author:** ![Pardee\_Roy](https://avatars.discourse-cdn.com/v4/letter/p/f0a364/32.png) [@Pardee\_Roy](https://discuss.rubyonrails.org/u/Pardee_Roy)\ **Post date:** [June 6, 2008, 10:43pm UTC](https://discuss.rubyonrails.org/t/help-with-include-on-active-record-finds/30338/6 "2008-06-06T22:43:34Z")
Ah--you're right about changing .count to .size. That does dissappear the count(\*) query. Thanks! Like I say--I do get the LEFT JOIN query. It's not as pretty as yours, but it's there:   SELECT `organizations`.`id` AS t0\_r0,         `organizations`.`name` AS t0\_r1,         `organizations`.`abbreviation` AS t0\_r2,         `organizations`.`city` AS t0\_r3,         `organizations`.`state` AS t0\_r4,         `organizations`.`crn_site` AS t0\_r5,         `organizations`.`created_at` AS t0\_r6,         `organizations`.`updated_at` AS t0\_r7,         `people`.`id` AS t1\_r0,         `people`.`first_name` AS t1\_r1,         `people`.`last_name` AS t1\_r2,         `people`.`birth_date` AS t1\_r3,         `people`.`organization_id` AS t1\_r4,         `people`.`created_at` AS t1\_r5,         `people`.`updated_at` AS t1\_r6   FROM `organizations` LEFT OUTER JOIN        `people`   ON people.organization\_id = organizations.id WHERE (`organizations`.`id` = '1') That's with rails 2.0.2 and mysql. What's your version & db? (There's no chance that you left off the 'has\_many :cart\_items' declaration in your cart class is there?) ---
**Author:** ![Frederick\_Cheung](https://sea2.discourse-cdn.com/rubyonrails/user_avatar/discuss.rubyonrails.org/frederick_cheung/32/3901_2.png) [@Frederick\_Cheung](https://discuss.rubyonrails.org/u/Frederick_Cheung)\ **Post date:** [June 7, 2008, 6:14pm UTC](https://discuss.rubyonrails.org/t/help-with-include-on-active-record-finds/30338/7 "2008-06-07T18:14:33Z")
> > Hi All, I am having trouble getting the :include option to work on my > > active record finds. They are not eager loading, adding the joins to the sql > > queries. Has anyone had this problem? Here is my query: > > > > @cart = Cart.find\_by\_id(session[:cart\_id], :include =\> > > [:cart\_items]) > > > > This is generating the following query: SELECT \* FROM `carts` WHERE (`carts`.`id` = 23) LIMIT 1 > > > > Rails is not eager loading the cart\_items which belongs\_to cart. > > Does anyone know why? > > Don't think it can. Not in a single query. You have one cart that > has many items. You can't return all of that in a single query unless you want to send duplicate rows for the cart for every row of the cart > item. That's what Rails used to do 🙂 Fred