In this lesson, you will learn how to use the Graphql backreferences created by Gatsby to get more data from a parent content type.
In this example, we have a lesson that references an instructor but the instructor content type does not have any data about the lessons that are assigned to it. Usually, you would create a reference back in the instructor content type to the lesson but this can cause a circular reference that's hard to maintain. Fortunately in the Gatsby data layer, GraphQL, we can query the parent node to get its data from its child. That's called backreference.