GraphQL can do anything that a REST API can do, it's just a different interface over HTTP at the end of the day. There's nothing that particularly links it to S

GraphQL can do anything that a REST API can do, it's just a different interface over HTTP at the end of the day. There's nothing that particularly links it to SQL or any other data store, though some tools might add that coupling, especially if they're "schema-first". You can write query and mutation resolvers that generically do read and write operations. The resolvers are just strongly typed functions - they take in user-provided inputs and return a defined output that users can select a subset of fields from (inputs/outputs are defined in your schema). As long as you can access your data from your backend (whether it's in a SQL db, mongo, s3, or some custom data structure) then you can do whatever processing you want in your queries and mutations.