What are Active Record associations in Rails?

What are Active Record associations in Rails?

Active Record associations in Rails are used to define relationships between different models, such as one-to-many or many-to-many.

Can you give me an example of a one-to-many association?

Sure! In a blog application, a Post model can have many Comment models. You would set it up like this: has_many :comments in the Post model.

How do I set up a many-to-many association?

For a many-to-many association, you would use a join table. For example, if you have Author and Book models, you can create a has_and_belongs_to_many association.

What are some common pitfalls when using Active Record associations?

Common pitfalls include forgetting to set up the join table correctly, not using dependent: :destroy, and not eager loading associations to avoid N+1 queries.