Rails: Searching multiple tables from one query

问题

How do I write condition statement in find or paginate method to allow users search in Project and Project Category names simultaneously?

Now my code looks like this

@projects = Project.paginate :per_page => 20, :page => params[:page], :conditions => ['name LIKE ?', "%#{params[:search]}%"]

So I have also Category table with name field. How do I combine those two names together in this search query?

回答1:

Assuming that your Project model has_many :categories:

@projects = Project.paginate :per_page => 20, :page => params[:page], :joins => :categories, :conditions => ['projects.name LIKE ? OR categories.name LIKE ?', "%#{params[:search]}%", "%#{params[:search]}%"], :order => 'projects.id DESC'

Change the :order above if/as needed.

回答2:

I would do:

@categories = Category.find :conditions => ["name like ?", "%#{params[:search]}%"]

Concatenate @projects and @categories, and then use the result as the final search result list.

来源：https://stackoverflow.com/questions/652933/rails-searching-multiple-tables-from-one-query