Over-fetching and under-fetching problems in GraphQL - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is over-fetching in GraphQL?

Over-fetching happens when a query asks for more data than needed, causing extra information to be sent and slowing down the app.

beginner

What does under-fetching mean in GraphQL?

Under-fetching occurs when a query does not request enough data, so the app must make multiple requests to get all needed information.

beginner

How does GraphQL help solve over-fetching and under-fetching problems?

GraphQL lets clients ask exactly for the data they want, no more and no less, which avoids both over-fetching and under-fetching.

intermediate

Give an example of over-fetching in a REST API compared to GraphQL.

In REST, a user profile endpoint might return all user info even if the app only needs the name. In GraphQL, the query can ask just for the name, avoiding extra data.

intermediate

Why can under-fetching cause performance issues?

Under-fetching causes multiple network requests to get all needed data, which slows down the app and uses more resources.

What problem does over-fetching cause?

A Getting too much data than needed

B Getting too little data than needed

C No data returned

D Data format errors

Over-fetching means the query returns more data than the app actually needs.

Under-fetching leads to:

A Multiple requests to get all data

B One request with all data

C No data returned

D Faster app performance

Under-fetching means not enough data is returned, so the app must make more requests.

How does GraphQL prevent over-fetching?

A By returning all data always

B By limiting queries to one field

C By caching data on the server

D By letting clients specify exactly what data they want

GraphQL queries specify exactly which fields to return, avoiding extra data.

Which is a common cause of under-fetching?

A Requesting too many fields

B Using GraphQL

C Requesting too few fields

D Using REST APIs

Under-fetching happens when the query misses fields needed by the app.

What is a benefit of avoiding over-fetching and under-fetching?

A More network traffic

B Better app performance and user experience

C Slower app loading

D More server errors

Getting just the right data improves speed and user experience.

Explain over-fetching and under-fetching problems in simple terms.

Think about asking for too much or too little data.

How does GraphQL help fix over-fetching and under-fetching issues compared to REST APIs?

Focus on how GraphQL queries work.