Solution:Step 1: Check argument name matchingThe query uses postId which matches the resolver's args.postId.Step 2: Consider data availabilityIf posts array is empty, find returns undefined because no post exists.Final Answer:The posts array is empty -> Option AQuick Check:No data means find return

[Solved] Given the resolver:function getPost(root, args) { return posts.... }and the query:{ getPost(postId: 3) { title } }Which of the following is a likely cause if the resolver returns undefined? | GraphQL

GraphQL - Resolvers

Given the resolver:

function getPost(root, args) { return posts.find(p => p.id == args.postId); }

and the query:

{ getPost(postId: 3) { title } }

Which of the following is a likely cause if the resolver returns undefined?

AThe posts array is empty

BThe argument name in the query does not match the resolver's expected argument

CThe resolver function is missing the root parameter

DThe query syntax is invalid

Step-by-Step Solution

Solution:

Step 1: Check argument name matching
The query uses postId which matches the resolver's args.postId.
Step 2: Consider data availability
If posts array is empty, find returns undefined because no post exists.
Final Answer:
The posts array is empty -> Option A
Quick Check:
No data means find returns undefined [OK]

Quick Trick: Empty data arrays cause find() to return undefined [OK]

Common Mistakes:

Assuming argument name mismatch
Thinking missing root causes undefined
Assuming query syntax error

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Given the resolver:

Step 1: Check argument name matching

Step 2: Consider data availability

Final Answer:

Quick Check:

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