MongoDB with GraphQL - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main purpose of using GraphQL with MongoDB?

GraphQL lets you ask for exactly the data you want from MongoDB, making data fetching efficient and flexible.

beginner

In GraphQL, what is a resolver's role when working with MongoDB?

A resolver is a function that tells GraphQL how to get data from MongoDB for each query or mutation.

intermediate

How do you define a GraphQL schema to fetch a list of users from a MongoDB collection?

You define a Query type with a field like users: [User], where User is a type matching MongoDB user documents.

intermediate

What is the benefit of using GraphQL queries over REST endpoints with MongoDB?

GraphQL queries reduce over-fetching and under-fetching by letting clients specify exactly what fields they want from MongoDB.

advanced

How can you handle MongoDB ObjectId fields in GraphQL schemas?

You can use custom scalar types or convert ObjectId to strings in resolvers to work smoothly with GraphQL.

What does a GraphQL resolver do when connected to MongoDB?

A Defines the GraphQL schema types

B Runs MongoDB server

C Fetches or modifies data in MongoDB based on the query or mutation

D Creates indexes in MongoDB

Resolvers are functions that fetch or update data in MongoDB according to the GraphQL query or mutation.

Which GraphQL operation is used to retrieve data from MongoDB?

A Query

B Subscription

C Mutation

D Directive

Queries are used to read or fetch data, such as from MongoDB collections.

How can you represent MongoDB's ObjectId in a GraphQL schema?

A As a Boolean

B As a list

C As an integer

D As a custom scalar or string

ObjectId is usually handled as a string or custom scalar type in GraphQL schemas.

What is a key advantage of GraphQL over REST when querying MongoDB?

A GraphQL requires no schema

B GraphQL lets clients specify exactly which fields to get

C GraphQL only supports mutations

D GraphQL automatically indexes MongoDB

GraphQL allows clients to ask for only the data they need, reducing unnecessary data transfer.

Which GraphQL type would you use to define a list of MongoDB documents?

A List

B Scalar

C Object

D Enum

Lists in GraphQL represent arrays, perfect for multiple MongoDB documents.

Explain how GraphQL resolvers interact with MongoDB to fetch data.

Think about how GraphQL knows what data to get from MongoDB.

Describe the benefits of using GraphQL queries instead of REST endpoints when working with MongoDB.

Consider how clients ask for data differently in GraphQL.