In GraphQL, a resolver is a function that is responsible for fetching the data for a field in a query or mutation. Resolvers are defined in the schema and are executed by the GraphQL server when a query or mutation is received.
Each field in a GraphQL schema has a corresponding resolver function that is responsible for returning the data for that field. The resolver function can retrieve the data from a database, a third-party API, or any other source, and return it to the client.
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