[Solved] What is wrong with this resolver that causes a runtime error? const resolvers = { Query: { userId: (parent, args) => { return parent.id; } } }; Assuming the root query has no parent object. | GraphQL

GraphQL - Resolvers

What is wrong with this resolver that causes a runtime error?

const resolvers = {
  Query: {
    userId: (parent, args) => {
      return parent.id;
    }
  }
};

Assuming the root query has no parent object.

Aargs parameter is missing

BResolver should not use arrow functions

CResolver must return a promise

Dparent is undefined, so accessing parent.id causes error

Step-by-Step Solution

Solution:

Step 1: Understand parent in root query
At root query level, parent is usually undefined or null.
Step 2: Identify error cause
Accessing parent.id when parent is undefined causes runtime error.
Final Answer:
parent is undefined, so accessing parent.id causes error -> Option D
Quick Check:
Undefined parent causes error = B [OK]

Quick Trick: Root query parent is undefined; avoid accessing its properties [OK]

Common Mistakes:

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