GraphQL and DQL are two “distinct realms”. GraphQL does everything automated because it is a separate application that aims to automate your API. Based in your schema Dgraph’s GraphQL implementation creates all resolvers and logic to “resolve” your datamodel.
DQL is like “MYSQL”, it’s a database language. And we don’t have all the features that exist in GraphQL. Well, they are different things. Since you are using GraphQL, stick to it. Don’t try to do anything in DQL if you don’t know what might happen. Doing this without having full knowledge of DQL can be dangerous and break your entire GraphQL structure.
DQL is like “RAW”, “work by hand”, while GraphQL is logic automation. You already have more than 90% of the work done that you would have if you were to do everything by hand. Coding GraphQL resolvers for other databases is Herculaneum work. Using Dgraph’s GraphQL saves you valuable time.
And, no, it is not a bug. Just different things.