Learning about the fundamentals of GraphQL
GraphQL APIs contain three important root types – query, mutation, and subscription. These are all defined in the GraphQL schema using special SDL syntax.
GraphQL provides a single endpoint that returns the JSON response based on the request, which can be a query, a mutation, or a subscription.
First, let's understand queries.
Exploring the Query type
The Query type is used for reading operations that fetch information from the server. A single Query type can contain many queries. Let's write a query using SDL to retrieve the logged-in user, as shown in the following GraphQL schema:
type Query {
   me: LogginInUser
  # You can add other queries here
}
type LoggedInUser {
  id: ID
  accessToken: String
  refreshToken: String
  username: String
}
Here, you have done two things:
- You have defined the query root of the GraphQL interface,...
