BelongsTo

If you have not read the HasMany guide, please do so before continuing.

From the example on HasMany, you can add @BelongsTo to define the Product to Store relationship.

@Definition()
export class Product {
  @Id()
  id: ObjectId;
 
  @Property()
  name: string;
 
  @Property({ type: () => GraphQLObjectId })
  storeId: ObjectId;
 
  @BelongsTo(() => Store, { from: 'storeId' })
  store: Store;
}

Resolve field

You will be able to resolve the store field on the Product type.

query {
  product(id: "000000000000000000000000") {
    id
    name
    store {
      name
      id
    }
    storeId
  }
}
💡

To prevent resolving the store field, set noPopulation to true.

@Definition()
export class Product {
  @BelongsTo(() => Store, { from: 'storeId', noPopulation: true })
  store: Store;
}

Ensure relationship

By default, you cannot create a Product with a storeId that does not exist. You can change this behavior by setting the skipExistenceCheck option to true.

@Definition()
export class Product {
  @BelongsTo(() => Store, { from: 'storeId', skipExistenceCheck: true })
  store: Store;
}
HasManyHasOne