java - Firebase 实时数据库中的节点是什么？

Question

在 Firebase 实时数据库安全文档中 https://firebase.google.com/docs/database/security/quickstart ，他们提到节点。但是，我似乎无法弄清楚 Firebase 中的节点是什么。谁能帮忙？

Answer 1

您应该阅读有关 structuring your data 的文档.如果您还不了解这一点，那么安全规则将很难推理。从该页面:

All Firebase Realtime Database data is stored as JSON objects. You can think of the database as a cloud-hosted JSON tree. Unlike a SQL database, there are no tables or records. When you add data to the JSON tree, it becomes a node in the existing JSON structure with an associated key.

和:

When you fetch data at a location in your database, you also retrieve all of its child nodes. In addition, when you grant someone read or write access at a node in your database, you also grant them access to all data under that node. Therefore, in practice, it's best to keep your data structure as flat as possible.

节点只是数据库中的一个位置，就像计算机科学中的其他树状数据结构一样。