In GraphQL, validation refers to the process of ensuring that a query or mutation adheres to the rules defined in the schema. This includes verifying that the query or mutation only accesses fields and types that are defined in the schema, and that the input values for fields are of the correct type and within the specified constraints.
GraphQL servers perform validation on all incoming queries and mutations to ensure that they are valid before executing them. If a query or mutation is invalid, the server will return an error, indicating which parts of the query or mutation are invalid and why.
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