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Help with has_one, has_many, belongs...
7 Posts
Help with has_one, has_many, belongs...

Hi everyone, i've working with rails and i can't understanding something...let me make it clear:

I have two tables, obviously two models:


id category_id


id description

One category can be used for many employes, and one employ belongs to ONE category.

how can i make that?

employ: has_one :category

category: belongs_to :employ


employ: belongs_to :category

category: has_many :employes

I need to do something that meke possible use "@employ.category" and thats return the category of the employ, and "@category.employes" and thats return all employes with that category.

Hope someone can help me =\


employ: belongs_to :category

category: has_many :employes

One very simple rule which will let you deduce the other relationships. The belongs_to declaration is always on the model which has the foreign key in its table. So here, @employees@ has the @category_id@ foreign key, so the Employee model will have the @belongs_to :category@ declaration.

I'm very unsure about your use of words like employ and employes. The usual here would be to have the @Employee@ model, with the @employees@ table and then, in @Category@ you would have a @has_many :employees@ declaration. If you really want an @Employ@ model and the plural of that is @employes@ then you'll need a custom inflection.

Thank's for the solution

Jason King,

Good Reply. we should fallow naming convention strictly in ruby on rails.

I have a similar problem. Am a newbe as well.

My categories are already created i.e

categories: id name

posts: id category_id title excerpt body ....

Category has_many :posts

Post belongs_to :category

How do I ensure that during the creation of a post, using a checkbox or radio button, the selected category is updated in the data base?

So that if I do @jobs.category.find(params[:category_id]) if this is right, I get a list of jobs under that category?

What should I do in the controller/model methods?

Sorry for my noobishness



Firstly if you are looking for all the jobs under a category I would suggest:


That will find the category of a given name and then all of the posts for that category.

When you are creating the post all you need to do is set the category_id to the category you want. I would suggest looking into "formtastic":http://github.com/justinfrench/formtastic to create elegant forms.

hope this helps

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