mutation CreateMovie ($title: String!, $released: Date!) {
createMovie (title: $title, released: $released){
id
title
released
}
}
[submitted data]
{
“title”: “Seven Samurai”
“released”: “1950”
}
All queries, including mutation queries, can return data. Here, the list of fields in the curly braces after createMovie specifies what we want to see returned from the server after a new record is created with this request. The value for the id field, in this case, would be created by the database; the values for the other fields are submitted in the query.
Another thing to keep in mind is that the queries and data types used to return data are by design different from those used to request data. Mutation queries need to validate incoming data, so the types used for those queries are meant to serve that function. Likewise, the fields used in returned query objects are for display, not validation. If you take in a GraphQL object as returned from a query, it might have fields with circular references or other issues that make it unusable as a query parameter.
Why use GraphQL?
A key reason to choose GraphQL over REST is the explicit, declarative nature of GraphQL queries. Having a formal definition for how queries and returned data should look has advantages aside from being consistent across APIs and implementations.
