Im confused when it comes to making an

@relation

... If I have a field in my datamodel.prisma like

type Item { parent: String! }

how can I change that so it becomes a relationship to another type. If I change it into

type Item { parent: Collection! @relation(name: "CollectionItemBelongsIn", onDelete: SET_NULL) }

... then I can no longer pass the field "parent" a String ?