如何删除 CKRecord 和 CloudKit 中的所有引用记录

Question

我想删除父 CKRecord 和这条记录的所有子。 创建父记录和子记录的方法如下：

func save() {
    //Creating parent record

    let parentRecord = CKRecord(recordType: "ParentRecord")
    parentRecord["name"] = "BOO" as CKRecordValue

    //Creating child record

    let childRecord = CKRecord(recordType: "ChildRecord")
    childRecord["name"] = "FOO" as CKRecordValue
    let reference = CKReference(record: childRecord, action: CKReferenceAction.deleteSelf)

    //ADDING Reference to parent record

    parentRecord["referenceObject"] = reference as CKRecordValue

    let operation = CKModifyRecordsOperation(recordsToSave: [parentRecord, childRecord], recordIDsToDelete: nil)
    //([CKRecord]?, [CKRecordID]?, Error?) -> Void)
    operation.modifyRecordsCompletionBlock = { records, recordIDs, error in
        if error != nil {
            print(error.debugDescription)
        }
    }
    operation.queuePriority = .high
    operation.qualityOfService = .background
    let operationQueue = OperationQueue()
    operationQueue.addOperations([operation], waitUntilFinished: false)
}

现在我只想通过代码删除父记录。由于CKReferenceAction.deleteSelf，应自动删除子记录。 “删除”函数如下所示：

func delete(recordName: String) {
    let privateDB = CKContainer.default().privateCloudDatabase
    let recordID = CKRecordID(recordName: recordName)
    privateDB.delete(withRecordID: recordID) { (id, error) in
        if error != nil {
            print(error.debugDescription)
        }
    }
}

当我使用 delete 方法时，我的 父 记录正在从 CloudKit 数据库中删除，但子记录仍然存在，我不知道为什么。有什么建议吗？

Answer 1

解决方案

如果我们想删除子记录，我们必须将parent record的引用添加到child record。在上述情况下，它应该如下所示：

    let privateDB = CKContainer.default().privateCloudDatabase

    let parentRecord = CKRecord(recordType: "ParentRecord")
    parentRecord["name"] = "FOO" as CKRecordValue

    let childRecord = CKRecord(recordType: "ChildRecord")
    childRecord["name"] = "BOO" as CKRecordValue

    privateDB.save(parentRecord) { (record: CKRecord?, error: Error?) in
        if error == nil {
            if let responseRecord = record {
                let reference = CKReference(record: responseRecord, action: CKReferenceAction.deleteSelf)
                childRecord["referenceObject"] = reference as CKRecordValue
                privateDB.save(childRecord, completionHandler: { (record, error) in
                    // DO SOMETHIG
                })
            }
        }
    }

在这种情况下，删除parent record会自动删除子记录