Rails协会(Rails Associations)

 我似乎无法绕过Rails关联。 假设我有3张桌子。 一个用于用户，一个用于食谱，另一个用于配料。 以下是数据库的示例（在yaml中）： 
 
Users:
  id: 1
  email: funnyusername
  password: pass1234

Recipes:
  id: 1591
  user_id: 1
  name: Pizza Dough

Ingredients:
  id: 1
  name: Flour

  id: 2
  name: Water

  id: 3
  name: Yeast
 
 现在我该怎么做，以便用户可以有很多食谱，一个食谱可以有很多成分。 还能够找到每种配料所附的所有配方？ 
 
 例如，funnyusername创建了配方“比萨面团”，其中配有面粉，水和酵母。 现在，当我搜索酵母时，我希望它能拿出一份包含酵母的食谱列表。 

I can't seem to wrap my mind around Rails associations. Let's say I have 3 tables. One for Users, one for Recipes, and one for Ingredients. Here's an example of the database (in yaml):
 
Users:
  id: 1
  email: funnyusername
  password: pass1234

Recipes:
  id: 1591
  user_id: 1
  name: Pizza Dough

Ingredients:
  id: 1
  name: Flour

  id: 2
  name: Water

  id: 3
  name: Yeast
 
Now how would I make it so that a User can have many Recipes, and a Recipe can have many Ingredients. And also be able to find all the Recipes each Ingredient is attached to?
 
For instance, funnyusername created the Recipe "Pizza Dough" which has the ingredients Flour, Water, and Yeast. Now when I search for Yeast, I would want it to come up with a list of Recipes containing Yeast.

原文：https://stackoverflow.com/questions/1414214