swift - CoreData 关系循环？

Question

我有 2 个实体 Buildings 和 GroupOfBuildings:

Building1 有:GroupOfBuildings1
Building2 有:GroupOfBuildings1

GroupOfBuildings1 有:Building1、Building2 和 Building3

关系:

Building <<----> GroupOfBuildings
Building <<--->> GroupOfBuildings
Building <---->> GroupOfBuildings

---

问题:

GroupOfBuildings 有一组 Buildings 可以在 Buildings 中使用，还包含一个 mainBuildings 引用建筑物。最重要的是，Buildings 需要对 GroupOfBuildings 的引用。这是建立关系的正确方法还是有另一种方法？似乎设置多个(循环)关系不是我应该做的事情。有什么建议吗？

---

示例代码:

let buildingDescription = NSEntityDescription.entity(forEntityName: "Buildings", in: context)!
let building1 = Buildings(entity: buildingDescription, insertInto: context)
let building2 = Buildings(entity: buildingDescription, insertInto: context)
let building3 = Buildings(entity: buildingDescription, insertInto: context)

let groupOfBuildingDescription = NSEntityDescription.entity(forEntityName: "GroupOfBuildings", in: context)!
let groupOfBuildings1 = GroupOfBuildings(entity: groupOfBuildingDescription, insertInto: context)

groupOfBuildings1.mainBuilding = building1
groupOfBuildings1.groupOfBuildings = Set([building2, building3])

building1.groupOfBuildings = groupOfBuildings1
building2.groupOfBuildings = groupOfBuildings1

---

注意事项:

我有另一个问题使用相同的数据，但问题不同。

Answer 1

由于命名错误，这很难理解。称呼事物本来的样子，不要将对象名称复数化。 Buildings 应该叫 Building，GroupOfBuildings 可能是 BuildingGroup，不知道“items”指的是什么...

也就是说，在相同对象之间建立多重关系是没有问题的。您可以使用 buildingGroup.mainBuilding、buildingGroup.otherBuildings、buildingGroup.extraBuildings 一切正常，只需正确命名它们即可。