GraphQL Query

A GraphQL query describes the exact shape of data you want back — nested fields and all — and the server returns precisely that, no more and no less. This solves REST's common over-fetching (getting fields you don't need) and under-fetching (needing several endpoints to assemble one screen) in a single request.

• —A query's shape mirrors the response's shape — what you ask for is what you get back, field for field.
• —One query can replace several REST calls by nesting related data (a post, its author, and its comments) in a single round trip.
• —Because the client controls the shape, the same endpoint serves a mobile app's lean needs and a dashboard's heavy needs without separate APIs.

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