Mutation syntax in GraphQL - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a mutation in GraphQL?

A mutation is a special type of GraphQL operation used to change data on the server, like creating, updating, or deleting records.

beginner

How do you start writing a mutation in GraphQL?

You start with the keyword mutation, followed by the mutation name and the fields you want to change or return.

intermediate

What is the purpose of variables in a GraphQL mutation?

Variables let you pass dynamic values into a mutation, making it reusable and flexible without changing the mutation code itself.

beginner

Explain the structure of a simple GraphQL mutation to add a new user with name and email.

A mutation includes the mutation keyword, a mutation name, input arguments like name and email, and the fields you want back, for example:<br>

mutation {<br>  addUser(name: "Alice", email: "[e-mail]") {<br>    id<br>    name<br>  }<br>}

intermediate

Why do mutations usually return data after execution?

Returning data after a mutation confirms the change and provides updated information, like the new record's ID or updated fields.

Which keyword starts a GraphQL mutation?

A change

B mutation

C update

D query

The keyword mutation is used to start a mutation operation in GraphQL.

What does a GraphQL mutation typically do?

A Fetch data without changes

B Delete the entire database

C Change data on the server

D Only update client-side data

Mutations are designed to change data on the server, such as creating, updating, or deleting records.

How do you pass dynamic values into a mutation?

A Using variables

B Hardcoding values

C Using comments

D Using fragments

Variables allow you to pass dynamic values into mutations, making them reusable.

What is the correct way to request the ID of a newly created user in a mutation?

A Use a special <code>getId</code> keyword

B Use a separate query after mutation

C Mutations cannot return fields

D Include <code>id</code> in the mutation's return fields

You include the id field in the mutation's return selection to get it back after the mutation.

Which of these is NOT a typical use of a GraphQL mutation?

A Fetching a list of items

B Updating existing data

C Creating a new record

D Deleting a record

Fetching data is done with queries, not mutations.

Describe the basic syntax of a GraphQL mutation and how it differs from a query.

Think about how you tell the server to change data instead of just asking for it.

Explain why variables are useful in GraphQL mutations and give an example of their use.

Variables help avoid rewriting the mutation for different inputs.