How do I access a child table/model from the parent in sql s

Rails
1

I am trying to use the fourth normal form for my applications so that i
can get the information in the appropriate language.

I have a table called manufacturers. I have another called descriptions.
The descriptions are in two languages and each description belongs to a
particular language. So two records in the Descriptions table one in
English and One in French for each manufacturer. The descriptions table
has the manufactturers id as a foreign key.

I have followed this for my Rails project but am stuck.

I have two models.

One is called Manufacturer.
One is called Description.

Manufacturer
has_many :descriptions

Description
belongs_to :manufacturer

In the manufacturers model I have the following method to look up all of
the manufacturers for the given locale.

def self.find_all
find(:all, :order => “name”, :conditions => {:locale => I18n.locale})
end

This produces the following error

Mysql::Error: Unknown ‘manufacturers.locale’ in ‘where clause’: SELECT *
FROM ‘manufacturers’ where (‘manufacturers’.‘locale’ = ‘en’)

how can I fix the sql statement in Rails?

Thank you in advance

Last edited by mitch_newbie (Today 07:24:24)

2

Something like this:

Manufacturer.all :joins => :description, :conditions => {:descriptions
=> {:locale => I18n.locale}}

3

Alexei Spirit wrote:

Something like this:

Manufacturer.all :joins => :description, :conditions => {:descriptions
=> {:locale => I18n.locale}}

Version with :order

Manufacturer.all :joins => :description, :order => :name, :conditions =>
{:descriptions => {:locale => I18n.locale}}

4

Alexei Spirit wrote:

Alexei Spirit wrote:

Something like this:

Manufacturer.all :joins => :description, :conditions => {:descriptions
=> {:locale => I18n.locale}}

Version with :order

Manufacturer.all :joins => :description, :order => :name, :conditions =>
{:descriptions => {:locale => I18n.locale}}

Thank you so much.

I did this based upon what you wrote above and it works great.

find(:all, :joins => :descriptions, :order => :name, :conditions =>
{:descriptions => {:locale => I18n.locale}})

Thanks again.

5

One last question.
I need the description for the manufacturer that is found in the table
descriptions. How do I get this columns info and how do I access it in
the view?

Thank you in advance

With this one:

find(:all, :joins => :descriptions, :order => :name, :conditions =>
{:descriptions => {:locale => I18n.locale}})
since you descript your associations you can get manufacturers with all
associated models, then you can use it anywhere

Like this one for example:

@manufacturers = Manufacturer.all :joins => :description, :order =>
:name, :conditions => {:descriptions => {:locale => I18n.locale}}

@manufacturers.each do |manufacturer|
puts manufacturer.description.description
end

6

Mitchell G. wrote:

Alexei Spirit wrote:

Alexei Spirit wrote:

Something like this:

Manufacturer.all :joins => :description, :conditions => {:descriptions
=> {:locale => I18n.locale}}

Version with :order

Manufacturer.all :joins => :description, :order => :name, :conditions =>
{:descriptions => {:locale => I18n.locale}}

Thank you so much.

I did this based upon what you wrote above and it works great.

find(:all, :joins => :descriptions, :order => :name, :conditions =>
{:descriptions => {:locale => I18n.locale}})

Thanks again.

One last question.
I need the description for the manufacturer that is found in the table
descriptions. How do I get this columns info and how do I access it in
the view?

Thank you in advance

7

I suppose this would very helpfull for u:

8

I suppose this would be very helpfull for u:

9

Alexei Spirit wrote:

I suppose this would be very helpfull for u:
Active Record Query Interface — Ruby on Rails Guides

Yes Alexei that is the perfect guide. Thanks again.