[Solved] Given this GraphQL schema snippet:type Author { id: ID! books: [Book!]!... }What will the query { author(id: "1") { books { title } } } return if author 1 has two books titled "A" and "B"? | GraphQL

GraphQL - Type Relationships

Given this GraphQL schema snippet:

type Author {
  id: ID!
  books: [Book!]!
}

type Book {
  id: ID!
  title: String!
  author: Author!
}

What will the query { author(id: "1") { books { title } } } return if author 1 has two books titled "A" and "B"?

A{"data":{"author":{"books":{"title":"A"}}}}

B{"data":{"author":{"books":[{"title":"A"},{"title":"B"}]}}}

C{"data":{"author":{"books":null}}}

D{"errors":[{"message":"Field 'books' not found"}]}

Step-by-Step Solution

Solution:

Step 1: Understand schema and query
Author has a list of books. Query asks for author with id "1" and their books' titles.
Step 2: Predict query result
Since author 1 has two books "A" and "B", the books field returns a list with both titles.
Final Answer:
{"data":{"author":{"books":[{"title":"A"},{"title":"B"}]}}} -> Option B
Quick Check:
List of books with titles A and B returned [OK]

Quick Trick: List fields return arrays of objects in GraphQL query results [OK]

Common Mistakes:

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