DQL to delete nodes + all child nodes with upsert

Users Dgraph
1

say i have this simplified schema in graphql:

type Folder {
    id: ID!
    title: String! @search(by: [exact])
    createdby: User!
    folders: [Folder] @hasInverse(field: parent)
    files: [File] @hasInverse(field: parent)
    parent: Folder
}

type File {
  	id: ID!
  	title: String! @search(by: [exact])
  	createdby: User!
  	parent: Folder
}

When I delete a folder I also want to delete all its children folders and files. I’m struggling to think of a recursive DQL query to solve this. I was thinking of an upsert with a recursive query to get all the UIDs of the child nodes and then somehow pass that to the delete mutation. for starters:

upsert {
 query {
   q(func: uid("0x2e357"))  {   // apply recursive query here to 
loop through all children
     Folder.folders {
       uid
     }
   }
 }
 
 mutation {
   delete {
       // triples with queried uids
   }
 }
}

any help to go from there would be great. i guess if too complicated I can generated RDF quads from the client side and go from there.

2

Are you inserting the data via GraphQL or DQL? if DQL, make sure your dataset has “dgraph.type” plus the value e.g: "{ dgraph.type": "File" },{ "dgraph.type": "Folder" }.

3

the DQL I used to solve this was:

upsert {
  query {
    q(func: uid("0x2e357")) @recurse @normalize {
      all_ids as uid
      Folder.folders
      Folder.files
    }
  }
  
  mutation {
    delete {
      uid(all_ids) * * .
    }
  }
}
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