[Solved] Why does this mutation cause an error?mutation updateUser($input: UserInput!) { updateUser(input: $input) { id } }When called without providing $input variable. | GraphQL

GraphQL - Mutations

Why does this mutation cause an error?

mutation updateUser($input: UserInput!) { updateUser(input: $input) { id } }

When called without providing $input variable.

ABecause mutation keyword is missing

BBecause $input is required but not provided

CBecause return fields are missing

DBecause variable name is invalid

Step-by-Step Solution

Solution:

Step 1: Check variable definition
$input is marked with ! meaning it is required.
Step 2: Analyze call without variable
Not providing $input causes error because required input is missing.
Final Answer:
Because $input is required but not provided -> Option B
Quick Check:
Required variables must be provided [OK]

Quick Trick: Required variables must always be supplied [OK]

Common Mistakes:

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