What is the purpose of the dataloader pattern in GraphQL?

• A. It batches and caches data fetching to minimize N+1 queries.
• B. It encrypts GraphQL payloads for secure transport.
• C. It ensures strict type checking on client side.
• D. It converts REST calls into GraphQL endpoints.

Answer: (A)

The dataloader pattern is about batching and caching data fetching to minimize N+1 queries. In GraphQL, a single query can trigger many resolver calls, and without batching you might end up querying the database once for each item in a list (the N+1 problem). DataLoader collects all the requested keys during a single operation and sends them in one batched request to the data source, such as a database, then maps the results back to the individual requests. It also caches results so that repeated requests for the same key within the same operation don’t hit the data source again. This dramatically reduces the number of queries and cuts latency for complex, nested GraphQL queries. The other options describe tasks outside what DataLoader does, such as encrypting payloads, enforcing client-side type checks, or converting REST calls into GraphQL endpoints.