Read-Through

1. The Pattern

The application only ever talks to the cache. On a miss, the cache itself fetches the data from the database, stores a copy, and returns it. The fetching logic lives in one place: inside the cache layer, not scattered through your code.

Recall the conclusion of cache-aside. Every data-access function contained repeated check, fetch, set, and return logic, while write paths that omitted their responsibilities created a predictable category of bugs