Problem using ActiveRecord find with :joins and :select

Rails
1

Hi guys,

When I do:

temp = User.find(:all,
:joins => “INNER JOIN contents ON users.agent_id =
contents.id”,
:select => “contents.id, users.id, users.u_date”)

temp.first.inspect

It seems to work fine, but it only returns:
#<User id: 6, u_date: “2009-10-03 19:32:23”>

but not the contents.id information.

I don’t get it, and I don’t know what to do to rectify this. It seems
like since I call find on User, it only returns infos related to this
model.
By the way, when I copy the SQL code generated by Rails directly in my
DB, it works fine and returns all 3 fields.

Do you have any idea what I am missing?

Thanks a lot!
Peter

2

Hiii
Active record → mapping rec on table to object

SO…

temp.first.inspect → user object

please try… temp.first.content.inspect—> will show contents.id

Note: first you must add relation between model user and model
content…

Thank you

On Mon, Oct 5, 2009 at 6:19 AM, PierreW [email protected] wrote:

temp.first.inspect
DB, it works fine and returns all 3 fields.

Do you have any idea what I am missing?

Thanks a lot!
Peter

–

Senior Rails Developer
Anton Effendi - Wu You Duan

3

On Oct 5, 12:19 am, PierreW [email protected] wrote:

Do you have any idea what I am missing?

attributes are stored in a hash, ie there can be only one attribute
called id - you need to alias the contents.id attribute. Even when you
do that, inspect won’t show the extra value, but temp.first.content_id
(assuming you alias it as content_id) should return the right id.
Lastly, what’s the point of the hoin to get contents.id when you know
the contents.id == users.agent_id ?

Fred

4

Thanks a lot guys for clarifying this. It worked with the aliases as
you suggested.

Fred, to your last point: sorry about that, you are right. I just made
up the example to show the mechanics, I didn’t realize it didn’t quite
make any sense.

Peter

On Oct 5, 8:37 am, Frederick C. [email protected]