How to update relational data in Graphql

I am new to Graphql and I want to update relational types, but I have no idea how to do it.

My type definitions are as following:

type User {
    email: String!
    username: String!
    password: String!
    registered_at: Date!
    role: String!
    Questionnaire: [Questionnaire!]! @relationship(type: "has_questionnaire", direction: OUT)

type Questionnaire {
    User: [User!]! @relationship(type: "has_questionnaire", direction: IN)
    id: ID!
    ClosedQuestions: [Answer!]! @relationship(type: "has_answered", direction: OUT)
    OpenQuestions: [BigInt]

type Answer {
    Questionnaire: Questionnaire! @relationship(type: "has_answered", direction: IN)
    id: ID!
    component: String!
    scope: String!
    answer: String!
    answered_at: Date!
  1. How would I write my mutation if I want to update the OpenQuestions list from a specific Questionnaire (id) from a specific user (username). My attempt was the following:
mutation {
        where: {
            username: „Kilian“
            id: „Project 1“      ##This id refers to the Questionnaire id
        update: {
            OpenQuestions: [2, 3]
    ) {
        users {
            Questionnaire {

/\ But this does not work…

  1. One step further/deeper: How would I write my mutation if I want to update a specific answer (id) within a specific questionnaire from a specific user?

Many thanks for your help! :v: