Batching and Request-Level Caching
DataLoader generally provides two important capabilities: batching and caching.
Batching combines multiple loads into one batch operation. Request-level caching prevents repeated requests for the same key during a single GraphQL operation.
For example, if five posts reference the same author, the application can load that author once and reuse the result. This is different from a long-lived application cache because DataLoader caches are normally scoped to a request.