Yep, GraphQL is agnostic as to how your data is stored. For example, https://github.com/graphql/swapi-graphql/ is a GraphQL schema that is backed by the swapi.co API. The examples at https://github.com/graphql/graphql-js/blob/master/src/__test... are backed by in-memory JSON objects. At Facebook, we have GraphQL types backed by data stored in a number of backends, including types backed by SQL tables.