Caching is one of the most effective levers you have for speeding up a Magento 2 store. But "caching" is not a single thing — it's a stack of overlapping layers, each operating at a different level of your infrastructure. Two layers that often cause confusion are MySQL's query cache and Magento's built-in cache . They sound similar, they both exist to serve data faster, but they work in completely different ways and serve completely different purposes.

This post breaks down exactly what each one does, where they overlap, where they don't, and how to configure them properly for a production Magento 2 environment.

What Is MySQL Query Cache?

MySQL's query cache is a server-level feature that stores the result set of a SELECT query alongside the raw SQL string.…