How does GraphQL address over-fetching and under-fetching in data retrieval?

How does GraphQL address over-fetching and under-fetching in data retrieval?

• A. GraphQL solves both by letting clients specify exactly the fields they need in one query.
• B. Over-fetching occurs when clients fetch no data.
• C. Under-fetching is when you fetch all data in one query.
• D. GraphQL always requires multiple requests.

Answer: (C)

GraphQL lets you specify exactly which fields you want in a single query, including nested related data. This means you pull only the data you need (avoiding over-fetching) and you can fetch related pieces of data in one round-trip so you don’t have to make multiple requests to assemble what you need (avoiding under-fetching). The idea isn’t that over-fetching means you fetch no data, or that under-fetching means you fetch everything in one go; those definitions are reversed. GraphQL typically reduces the need for multiple requests by letting you request the complete, needed shape of data in one query.

GraphQL lets you specify exactly which fields you want in a single query, including nested related data. This means you pull only the data you need (avoiding over-fetching) and you can fetch related pieces of data in one round-trip so you don’t have to make multiple requests to assemble what you need (avoiding under-fetching). The idea isn’t that over-fetching means you fetch no data, or that under-fetching means you fetch everything in one go; those definitions are reversed. GraphQL typically reduces the need for multiple requests by letting you request the complete, needed shape of data in one query.