IIRC in the Gatsby framework it has a built-in GraphQL parser for server-side developers to query data from Gatsby plugins, which can be things like data stores, other APIs, or even a mixture and blended together.
In a way, that's using the server as a client for other servers, ie it would be the same as a server sending a REST request to another server asking for data. What I mean is nowhere should there be GraphQL between a server and a database, because that doesn't make any sense, just use an ORM.